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Thread: heater hose exploded, hard start, low power in low rpms

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  1. #1

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    heater hose exploded, hard start, low power in low rpms

    Steam out from under hood, found the culprit being a 4" blowout hole of the heater hose running from carb area to firewall. Checked the coolant level in the radiator and it was low, but the fins were still wet so it didn't even get hot enough to evaporate dry.

    Replaced hose with a fix it kit type thing using a new section of bulk heater hose & a plastic adapter piece just to be able get it home, refilled coolant but it only took just under a gallon, started right up nice, but black smoke out of exhaust 3 miles home, very low power in low rpms had a hell of a time getting it up to speed like it wasn't responding to the gas pedal, but get it up to 40mph & it has a bit of power even with the black smoke still sort of visible in the mirror during panicked 'omg just get me home' driving.

    Died a few times at idle(red-lights) and had hard restarts on the way home. Simply didn't want to start back up & ran like crap when it did,all the way up to about 35-40mph. Then back down at lower speeds it was miserable to keep the rpms up, though no backfiring.
    Pretty much solid black stuff out the tailpipe the whole way home though.
    No weird engine noises though & the oil looks fine.
    Ran but super rough and is very very unhappy but she made it up my steep 30' driveway section thankfully.

    Checked the coolant in the radiator and overflow and no cross-contamination after it cooled off in the driveway.
    Pulled the oil cap off and it was not foamy (YAY!) and not yucky in any way though it smelled a bit like gasoline to me --- it has for a long time now and it's been running practically perfectly so I didn't worry about it until now thought I'd mention it just in case.
    Air filter is a little dirty but looks like a normal "almost time to replace it" air filter, nothing screaming "'omg' that's filthy".

    The bulk heater hose used as a temp-repair is kinked a bit in 2 places from the 'just get us home' repair in the parking lot. That needs to be redone or replaced with the molded hose that should be there, will get to that in the morning. Obviously the path of the coolant was restricted (though not completely blocked) on the way home, but the temp gauge only went up about 1/4" from the 3 mile trip home & it took a long time for it to start moving at all. No temp spikes.

    But why oh why is it running like crap now??? It didn't overheat according to the temp gauge, the oil isn't saying I blew a head gasket which is what I was scared of with the lack of power at low rpms/speeds.



    So these are all the panicked thoughts I'm having:

    I don't think I touched anything else other than taking off the air filter housing and the heater hose. When I first was looking around to see where the steam was coming from everything looked GREAT. No oil leaking, no obvious signs of overheating or leaks anywhere, until I found the heater hose had exploded. I didn't mess with a anything else just replaced that hose section.

    Wondering if the pressure of the fluid when the hose exploded could have damaged something around the carb (under the air filter area), or what in the hell probably happened.

    How would loss of some coolant cause a super rich condition? Or is that even possible? Makes no sense so hoping for any ideas.

    The truck was running fantastically wonderful before this happened so no idea what I could have done wrong/vacuum lines accidentally bumped by me or ruined when the hose let go?

    Is there an electronic anything that could have been damaged by the sudden burst of coolant in the wrong direction?

    Will look for signs of vacuum hoses being damaged, re-do that kinked heater hose, Maybe try to run it & see if there's air in the cooling system to be burped out? maybe check the plugs??? but they're likely to be filthy with it running so rich anyway so I don't know if that would be useful to see anyway.

    Does coolant actually run through the carb??? If so, what sort of damage to the carb happens when it runs without coolant at 35mph for simply just 2 minutes to coast into a parking lot? Heck, I don't know if it actually ran without coolant anywhere because it only took about a gallon & I'm pretty sure the capacity is much higher than that.

    How does it make sense that it started right up when it was cold in the parking lot right after the repaired hose was done, but it hated restarting after it died at red lights on the way home?

    If I do restart it tomorrow I'll make sure I do it with the heater turned on & fan off, just in case that helps circulate coolant through the 'new' heater hose section, etc. Disappointed in myself I didn't think of making sure the heater was on today on the way home after the repair. WAs too concerned to be able to listen for any weird engine noises so had all accessories off on the way home.

    ^ these are the things I'm thinking of & types of videos I've spent tonight looking at so far.

    I'll update after I look at it again tomorrow but I'm scared to run the engine with it running so miserably because I don't want to do any further damage Looking at it today I simply didn't see anything "wrong", leaking, or out of place

  2. #2

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    O.k. I'll give this a shot tink. Coolant does go through the carb but only in through the auto choke mechanism. Coolant also goes through the base of the carb in a chamber under the plenum in the manifold. If it runs dry it won't damage the carb. Please say you didn't fill the radiator while the engine was hot - this would be enough to split the head (even if it showed it didn't bake on the temp gauge). So you don't have any cross contamination of fluids in the engine which is a good sign. Could be that the carb happened to choose a time to quit completely when you had a cooling system fail. If the choke has decided to stay shut it will ruin the way the engine runs (you'll get all the symptoms you're experiencing - running way rich, no power on throttle etc) Pull the air filter box off, start it when it's dead cold and watch the auto choke butterfly. If it doesn't move or moves very little in the normal time it would take for the engine to warm up then you have found the culprit.

  3. #3

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    Quote Originally Posted by geezer101 View Post
    Please say you didn't fill the radiator while the engine was hot -
    I didn't fill the radiator while the engine was hot - it had sat overnight and was super cold.

    Giant thanks for taking the time to comment, I will try what you said & let you know, too

  4. #4

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    Hope it's only a carb issue as this is a minor thing compared to a cracked head. If you live in an area where emissions aren't checked and the Mikuni has finally died, it might be time for a Weber.

    p.s. if you ever get in a situation where the engine has overheated, pour water over the radiator while it's still running. Get it to flow through the radiators' cooling fins. It will bring the engine back down in temp safely and allow you to add water/coolant into the system gradually.

  5. #5

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    Thank you for the tip!

    With the new hose attachment, I started the truck with the radiator cap off so I could watch for air pockets effect on coolant level & the heater on but fan off.

    I watched the butterfly valve, it was shut before I started the truck, then barely opened after the truck started, after the temp gauge started to move when the engine finally started warming up, the butterfly valve thing didn't move at all. It stayed in the same position it was in at fast idle even when the engine went into it's normal operating temp rpm... then the engine started to run badly again, a little steam started to come out of the exhaust pipe, and the engine died, and THEN a whole bunch of coolant disappeared.

    Now I guess I'm waiting for the engine to cool down again, will top off the coolant, and try again.

    I'll see what I'm supposed to do about that butterfly valve, but I'm not sure if the carb is to blame if the coolant wasn't in the hoses that push it through that choke area, maybe that's why the valve didn't move. More learning for me to do.

    Oh and when I took off the temp heater hose, it was bone dry inside. So that means on the way home there was no coolant running through the carb's choke area (presuming if it did have coolant it didn't get hot in the hose to make it all evaporate). Though it wasn't even slimy inside like there was no coolant residue inside.

    By the way, it started right up on the cold start & ran great until it warmed up & died.

    Much appreciation for the tips!

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    symptoms mentioned may be due to "airlock". if the carburetor hoses are blocked of flow by an air bubble (airlocked) the choke will not operate correctly. try "bleeding" air out by loosening hose connections.

  7. #7

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    Quote Originally Posted by ragragtimetime View Post
    symptoms mentioned may be due to "airlock". if the carburetor hoses are blocked of flow by an air bubble (airlocked) the choke will not operate correctly. try "bleeding" air out by loosening hose connections.
    That's a really good idea! Wish I would have thought of that, will try that, too... I'm VERY interested to see what happens Thank you! ~ will update.

  8. #8

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    Looks like you know what you're doing. Does the heater work? I have seen some nasty things come out of heater cores - mud (yes, MUD) big chunks of iron oxide, calcification, stuff that looked like driveway gravel... anyway I would disconnect the heater hoses, flick the heater control to hot and jam the garden hose through it. Do it from either hose to flush it out, reconnect it (leave the heater control set to hot) and then disconnect the small hose from the heater connection barb at the back of the inlet manifold (the one to the auto choke) and refill the radiator until you get a little coolant overflow from the hose. It can be tricky getting air out of the cooling system of older vehicles. You also might have an issue with the inlet manifold too. They can get similarly blocked up with debris through the plenum base and the bypass gallery that goes towards the thermostat housing (to the point where the debris stays trapped in the manifold and begins to eat holes through the base plate that is welded on to the bottom of the plenum - not good!) Your sudden loss of coolant does not sound good. Check your spark plugs. If any of them look super clean it will indicate a blown head gasket.

  9. #9

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    Yeah I agree that heater core should be flushed while I'm messing with hoses in that area anyway... I even looked at rockauto to see if I could get a new heater core lol, just in case it wants to be a problem now that it has had no coolant running through it. I didn't see any listed there, but not majorly surprised. Was thinking about flushing it during this problem but really want to get it running reliably again before I get too far distracted with other things and end up pulling everything apart. I'm sure you know the "trap" of "might as well..." and ending up going from a 30minute fix it to a 3 day cleaning / adjusting / mod spree.

    I'm not too concerned about blockages in the manifold unless they came from the heater core (if that's possible) since I just had it off & cleaned it earlier this year. I'll have to check and see if it was the hose to OR from the heater core that exploded.

    If their was a bunch of air in the system... which wouldn't surprise me that would be a great non-problematic way to explain the coolant drop at the shut off but I don't like it all at once like that either. Usually it seems (on newer cars) while trying to burp the air out of coolant hoses the coolant loss is a little at a time. I don't understand the possible airlock/air bubble /vacuum situation that could have made the coolant level drop suddenly at shut-off. But again, I'm not very familiar with this g54b.

    Am thinking I'll pull off a heater hose at the firewall and see if the coolant managed to get that far before I add more coolant/water & start her up again. I did stuff a funnel into the top of the carb where the heater core attached & added water up to the end of the hose before I clamped it hoping to speed up the process of getting the air out by filling the gap with fluid so I didn't add air into the system with an 'empty' heater hose.

    I'm a bit concerned that the wax might have overheated w/no coolant in there & leaked out somehow based on pennymans post on another thread about the brownish goopy stuff visible on the linkage side of the carb when the auto choke fails. But I'm JUST GUESSING. I'll take a look in the daylight - or maybe later tonight if the damn rain stops, because that would be a game-over indication.

    Just popped outside to see if it was still raining hard thinking I could pull the plugs tonight maybe & I peeked at the oil cap for any bad signs while I was there ... procrastinating to peek at the plugs until the morning. Just one more thing to worry about until dawn. On the other hand, if it is the head gasket at least I know how to do that, haha!

  10. #10

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    There is nothing particularly unique about the 4G54 engine except those !@#$ing balance shafts which can cause grief if they're not installed properly. Pennyman is right about the brown greasy stuff - it is usually a give away that the auto choke has failed. If you see it + no choke shut off means you're either finding a serviceable Mikuni to swap onto your engine or an alternative carb. I've attempted removing the wax pellet assembly and other than destroying a dead auto choke I've found they would be near impossible to replace. Funny thing is the wax pellet assemblies are still available.

  11. #11

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    I still can't sleep, still reading interweb comments about related issues & thank you for the info on the wax assembly! I had no idea they were still available! Unusable stuff is a great way for me to learn sometimes. So if it is that, I'll still try to fix it but not hold my breath, either. I like your phrase "other than destroying a dead auto choke" ha! exactly what I've done, too: broke already broke things lol. Worth trying though, just in case we find a trick to make it work Like fixing the fan clutch/clutch fan (can never remember the order of the words), that ended up working out great though just by cleaning & lubricating the stuck spring in the middle. There always seems to be info experienced people have that aren't written in book pages!

    The one bit of good news that I found about that sudden coolant level drop in the radiator said:

    "You'll notice that during that time the coolant level might suddenly drop. This is because the thermostat opened up and is now allowing coolant flow."
    -- I don't know if it's okay to post the page I found it on another website so I won't just in case it's not ok.

    But that almost makes sense to me, since there was no sudden drop or really any drop at all up until the point the engine went from fast idle to normal idle , the choke didn't open & the engine died. If the thermostat usually opens up around the time the idle goes from fast to normal after a cold start up, then the timing of the sudden drop in coolant would make sense to me.

    I may also be being unrealistically optimistic dreading that a bunch of coolant got sucked into the cylinders, ha! Though considering there MUST have been air in the system since the heater hose was dry between the temp fix and when I got it home, it makes sense that there would be air pockets in hoses, etc. On the other hand it may have overheated & headgasket blew while I was waiting for it to warm up enough to get off fast idle. Sure would have expected the temp gauge to show something though it could have been in an air pocket itself perhaps. I was feeling the valve cover the whole time and it didn't even get warm (seriously never got 'hot' to the touch) and didn't even get warm until just before the rpms lowered from fast idle rpms.

    I don't mind looking dumb while trying to figure stuff out It always helps me to get ideas when I read others postings to understand the possibilities. So maybe my posts can help someone keep from going the wrong directions or even point them in the right ones by the time this gets sorted out.

    Thank you very much for taking the time to help me through this & keeping good conversation, too! It's amazing how something as simple as a blown hose can cause so many different things to happen.

  12. #12

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    Quote Originally Posted by tink View Post
    I don't mind looking dumb while trying to figure stuff out It always helps me to get ideas when I read others postings to understand the possibilities. So maybe my posts can help someone keep from going the wrong directions or even point them in the right ones by the time this gets sorted out.
    If you're looking for answers and not blaming 'that stupid POS truck' then you're a long way from dumb. These engines don't have any real inherent design flaws that cause them to mysteriously turn into a grenade and explode when you need it least to happen. Usually abuse or lack of maintenance that'll kill them. When we're not leading you on a wild goose chase I've found this forum and the members that contribute to it a really decent bunch of people.

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    For anyone else redoing heater hoses for the first time, see page 24-2 and 24-5 (step 2 referencing water valve) at: http://www.mightyram50.net/d-50/Fact...ERS_AND_AC.pdf (learn something new everyday)
    Last edited by SubGothius; 01-24-2023 at 01:09 PM. Reason: Fixed broken link

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    Quote Originally Posted by geezer101 View Post
    If you're looking for answers and not blaming 'that stupid POS truck' then you're a long way from dumb. These engines don't have any real inherent design flaws that cause them to mysteriously turn into a grenade and explode when you need it least to happen. Usually abuse or lack of maintenance that'll kill them. When we're not leading you on a wild goose chase I've found this forum and the members that contribute to it a really decent bunch of people.
    Yeah I really like these engines not just for the simplicity of them but because other than the jet valves they seem pretty darn reliable (if the maintenance is kept up). I'm determined to make this one dependable enough for long long road trips & learning the ins & outs of it will help if there ever is a problem in the middle of nowhere lol.

    I was thinking, too, if I knew the heater hose part of the system flow I could have looped the good hose back in to the blown hose connection point & just ran without a heater to make it back home, too. But the hose was so old it probably wouldn't have made it very far being configured & twisted around too sharply. Basically keeping the flow of coolant for the engine's sake, but with bypassing the heater core. If I ever blow another one of those hoses, I'll know that's an emergency option.

    Sometimes yeah, wild goose chase, or just so exhausted about the fiddly bits that some people suggest just bypassing things, blocking off plates or of course "just" put in a new carb. Hey I agree with that and if I had the money laying around & time to strip things off & etc, it probably happen. Yet I LIKE making things work the way they should and try to do that first. Sometimes I learn it's just not worth it though haha ---after banging my head against a wall for a while first.

    It's not the truck's fault though, it never is a stupid pos truck, it's a dang good truck, mine is a prime example - rare maintenance done on it & bandaids galore & just about every part was rusting out YET IT STILL RAN DAILY when I bought it. That for sure isn't a POS truck to me. With a little bit of better maintenance in my learning curve it seems it should run until the body rusts out completely.

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    All the air is out of the coolant system now & it runs good again. No smoke or steam out of the exhaust on the test drive up to 50mph even. So looks like she's all better now ~ Thanks again for the help!!!!

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    Quote Originally Posted by tink View Post
    All the air is out of the coolant system now & it runs good again. No smoke or steam out of the exhaust on the test drive up to 50mph even. So looks like she's all better now ~ Thanks again for the help!!!!
    Awesome! Good to hear. How is the carb situation? Persistence does pay. The Mikuni is not a fun thing to pull apart and rebuild and I would definitely not recommend someone who hasn't stripped a carb before to pull this thing off their engine and take it apart without having a spare one handy. I would get one that looked tired and do an autopsy on it to see how its assembled and have a guide available while stripping it. A kit and a huge clean helps but it is usually the auto choke and the vac can on the secondary throttle butterfly that fails on these.

    I have said it a number of times that I'm not a fan of the 4G5x engines because of my disdain of timing chains and the amount of work needed to replace them compared to a belt driven 4G6x. That being said, the Astron can handle scary amounts of abuse and neglect (they'll keep plugging along even when you can hear the timing chain flapping in the breeze) and the bottom ends are HD engineered. A friend of mine recalled that a healthy stock bottom end on these engine will hold its own in a fight up to 600 HP (geez, what were they thinking...) Not many 4 cylinder engines would handle half of that before bad things would happen to them.

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    Quote Originally Posted by geezer101 View Post
    Awesome! Good to hear. How is the carb situation? Persistence does pay. The Mikuni is not a fun thing to pull apart and rebuild and I would definitely not recommend someone who hasn't stripped a carb before to pull this thing off their engine and take it apart without having a spare one handy. I would get one that looked tired and do an autopsy on it to see how its assembled and have a guide available while stripping it. A kit and a huge clean helps but it is usually the auto choke and the vac can on the secondary throttle butterfly that fails on these.

    I have said it a number of times that I'm not a fan of the 4G5x engines because of my disdain of timing chains and the amount of work needed to replace them compared to a belt driven 4G6x. That being said, the Astron can handle scary amounts of abuse and neglect (they'll keep plugging along even when you can hear the timing chain flapping in the breeze) and the bottom ends are HD engineered. A friend of mine recalled that a healthy stock bottom end on these engine will hold its own in a fight up to 600 HP (geez, what were they thinking...) Not many 4 cylinder engines would handle half of that before bad things would happen to them.
    Well I watched the carb & butterfly valve positions like a hawk after fiddling with linkage to make sure things weren't kinked or 'stuck'. Found it a bit irritating that parts (screws, etc.) were hard to find and/or see on the firewall side & the valve cover side. I went so far as to take a house vacuum cleaner out there & stuck the hose on the choke side in case there was debris in there - probably not a popular thing to do but I did it with the engine off. I guess carb cleaner is the way to go but not knowing what was going on & having fear of fire I left out the solvents & cleaners for another day.

    I did pull off the heater hose (AGAIN) above the junction on the back of the carb (unsure how to explain that) thinking I'd stick my finger in the hole and make sure it was wet inside. Turned out when I pulled off the hose I could see the coolant in there & it was only down about 1/4" from where the hose gets clamped on. GREAT! Then used a funnel to pour a little bit of water into the heater hose itself before re-clamping that on. My thinking was if I could reattach things with the least amount of air in hoses possible then it would be easier to get any air pockets out.

    I was scared to death of running the engine it with no coolant in all the passages where it should be. So just to be sure, I pulled off the thermostat housing (where the thermostat sits not where it attaches to the head) to make sure there was coolant in there past the thermostat and boy howdy was there ever. AND it was clean coolant, so that was a relief. Picked up a new gasket for that at the parts store during the test drive, too.

    I considered pulling the plugs to look but those plugs have fooled me before. Once when I was checking them after the head gasket job was done & paranoia set in - I was checking plugs often, oil & coolant every morning & all other fluids multiple times per week. One time the plugs were all dirty and I freaked out. I went and got new plugs, came home, pulled the old ones and they were all clean!!! Lesson learned for me is they can be tricky.

    After a test drive today to the parts store (since that's a handy place to find a problem), I pulled the air cleaner top off & I'll be darned that choke wasn't exactly how it was supposed to be, wide open. Seriously confused that I could be so lucky, but their was very little condensation steam out of the exhaust, and no black or white smoke or steam or anything. It's like something I did made it run smoother than it did before. Weird, but nothing on the carb had to be adjusted after all!



    That's kind of ironic that you don't like the engines with the chains for the same reason that I don't like my other mitsubishi engine ( 6G72 ) that has a belt, haha! "the amount of work". Yes, and the exact tightness that it needs to be on, too, from all I've read it's not very forgiving so there's no way I'd try to replace it myself. I need something I can be "just about 100% right", not having to be "exact". I think the chain would be easier for me on the truck so was super happy to find this little truck.

    I would love love love to find a carb I can tear in to... and should now that you mention it! There's a junk yard not far from my house, I wonder if they'd be up to letting me get one, hmmm. I know one day this one will fail and yes, I'd probably like to put a weber on it eventually... or something super fancy, but not until I understand what's what. Wouldn't want to wear out anything prematurely by adding on too powerful of things that don't match up to what the engine & systems were originally built in to this truck.

    I've already had a sports type car, and frankly it's kind of nice to chug along at 55/60 and not have other drivers trying to race me or tailgating expecting me to go way over the speed limit, lol. It's so nice to drive this truck & even park in peace - people don't randomly come up and start asking me about her. The higher hp options are great for sure, but... it's really not the reason the truck is attractive to me. Though it's awesome that this sounds pretty much bulletproof I'll have to look up what "HD engineered" means though *blush*. Sooner or later I'll get all the abbreviations down.

  18. #18

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    You'll have no issues with blasting carb cleaner all over the Mikuni - it'll do it some good. And a shot of WD spray on linkages/moving parts. Sometimes it's enough to get it behaving itself. If you have a suspicion that the jets are clogged and you want to test that theory, you can do a 'purge'. Pull the air filter off, start the engine and then cup your hands over the throats of the carb (not enough to stall it, just enough for it to go mental and pull heaps of fuel up into the throats in one shot). This will normally force any fine debris that might be in the jets out and down the throats.

    Another test for carb health is the accelerator enrichment jet test. This one is easy but you may need a good light source just in case.- filter off, engine off and hold the choke open with a finger or something that won't damage it. Give the throttle linkage a quick turn and you should both see and hear a squirt of fuel into the primary throat. If you don't get the stream of fuel, the accelerator pump diaphragm is kaput (if you see a 'sort' of spray of fuel instead of a stream either the jet is partially blocked or the diaphragm is stretched). This jet adds a shot of fuel when you first hit the throttle. If the engine is a little hesitant from closed throttle that would indicate there's a problem with it.

    p.s. 'HD' = 'Heavy Duty'. Condensation from the exhaust = healthy engine. Man, you write up some long posts lol

  19. #19

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    G54B
    It's good to know about that diaphragm thank you very much for mentioning it! Next time there's a problem I'll know likely why.

    Wasn't sure about carb cleaner and little vacuum hoses getting damaged, so I haven't cleaned the outside of the carb at all - like ever. There was a little very fragile looking bit on it, covered with dust/dirt that I touched once to see if it was dead (lol, or moved, etc.) and was afraid it would fall apart. Dust flaked off of it in a way that seemed it's made of pure dust. I couldn't find a recent picture of it, but here's one from March before I tore the engine apart & replaced a ton of vacuum, etc. hoses:

    fragile_bit_on_carb.jpg

    I'm not sure what that is in the red circle, but I'm pretty sure if it got wet... I'd need to learn how to replace it the same day.

    Will do that WD spray on the linkages since there's not much rubber back there That's really good idea especially w/winter coming fast, thanks so much for the tip! That reminds me I need to do the door lock / handle areas, too.



    Ummm, I didn't mean to make this so long, you're so dang smart though wow so I really appreciate all the info & don't want to miss anything I'll have to start up a new thread when I get into the carb stuff since this is SUPPOSED to be about a hose haha!

  20. #20

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    O.k. the mystery object in your image is a vacuum barb connector. It is a plug that hooks up 3 vacuum ports to all the ancillary vac units on the engine. If it is perishing then it'll suck air into the system and bypass all the vac operated components (this in turn will mess with how the carb works and disable the ancillary vac stuff). Please oh please give this horrid carb a clean! If it runs worse I think it'll be due to the dirt blocking up the cracks in that barb connector being cleared out.

    Once it's clean go over the whole carb and check all the screws holding the top of the carb down and the mounting bolts (the 4 main ones you see from the top). No doubt you will find some of them are loose (sometimes a half turn loose is all it needs to start sucking air from everywhere it shouldn't). Nip them up until they are firm - no need to go hulk mode on them. The other screws will refuse to budge and you'll end up stripping the heads out of them. Nearly everyone who has gone to rebuild one of these carbs has chewed the tops out of screws on these...

    p.s. thanks for the kudos tink. I don't think my invitation to MENSA has been approved yet due to the number of times I've looked like a monkey swinging a hammer lol.

  21. #21

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    * I am only taking a guess at what I'm looking at in the supplied image - it really is filthy! I appears to be in the right location for the tri-hose vacuum connection thingamy.

  22. #22

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    1984 Mitsubishi Mighty Max
    Engine

    G54B
    Ah-ha! The vacuum barb connector is the squishy part! It is horrid looking yes, agreed... sort of figured the dust is the only thing keeping it together & any air leaks plugged, which is why I mentioned not wanting it to get wet... man I know it looks bad. My dad was supposed to be around to help me with it, he used to always rebuild these darn things & drive my mom nuts. Anyways, I'll have to clean it 1 screw area at a time, so if/when I mess something up I'll know exactly what.

    Will be very very careful with the head bits ~ thank you for the warning! 1 of my specialties around the house is ruining screw heads! Oh and prying ... I don't do the monkey hammer act but I know the monkey prying with a screwdriver routine quite well

  23. #23

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    Don't stress about using carb cleaner as it is intended for this job. There are wires, electrical components, plastic and rubber parts on a carb and the carb cleaner would be useless if it damaged any of these components. The squishy 'thing' might be some kind of dust boot that is located next to the vac connection. If it disintegrates it won't kill anything - just means whatever it is covering will be more exposed than what it is already.

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