engine startup- growly noises-intake whoosh-vibrations

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11-14-2017, 02:15 PM
2nup350

engine startup- growly noises-intake whoosh-vibrations

put in my used 2.6- it has better compression, doesn't smoke, has the non-jet head, Weber carb.
it "growls" at anything over idle- not unpleasant but it's way noiser than my old tired stock engine that was VERY quiet. why?
along with the growl is a buzzing vibration, felt through the foot, steering wheel etc. THAT is unpleasant, no idea where it comes from.
the Weber has a serious intake noise, anyone have tips to kill that?
Is there a way to see if the engine has the balance shafts installed without taking the motor apart? Maybe my noise is because of them being gone?
motor makes manly loud noises, but it doesn't seem to be super powerful. if it's not going to be fast, it should be quiet. any help wanted.
11-14-2017, 03:37 PM
BradMph

Any chance of running some video on this and posting in forum. Also to check for balance shaft, I thought if it didn't have one, they added a modification to the sprocket in the timing cover that made it just and idler type sprocket instead of the end of the balance shaft itself have the sprocket and chain on it.
If I remember on a g63b, there was a screw jammed into the short block that could be removed. I would check the sprocket though for a shaft end or idler type if I am not mistaken. Possible look to see what procedure is on removing and see what is replaced and removed for the shaft removals.

On Weber, are you 100% its a true Weber and not a imitation. There should be the word Weber on the fuel housing casting. Depending on the age of the Weber, the throttle shaft bushings can get old and maybe leak. Vacuum leaks around carb.

I would try running a video though so we can give it a listen. Check chain tension and make sure chain cover is not rubbing against any moving parts. Pulleys etc. Over tightening the cover can sometimes bring it into the moving parts.

Keep us informed.
11-14-2017, 07:42 PM
ragragtimetime

water pump failing?....easy to check for play at fan.
11-15-2017, 01:38 PM
2nup350

UPDATE- it's not a water pump, brand new and disconnecting the belt did not change anything. It is a Redline Weber from Spain- I checked that today. I did find a carb base leak-whistle that I fixed- and the idle got worse!. no amount of mixture tuning will keep the idle from vibrating like crazy unless i just crank the base idle over 1k. I rechecked the timing- 8 deg. and swapped out the plugs( I had planned on doing that anyway) It's not like a misfire- it's just uncouth. Idle vibrates the steering wheel and floor until the gauge needles bounce. the acceleration is good compared to my worn out old oil leaker, but it makes lots of noise and vibration to get there. The guy I bought it from swears the balance shafts are still in it- could they be installed off a tooth? way to check that without removal? I'm not a Noob and I know my way around engines, but I have little experience with these motors Dodge V8? Ford? no troubles!- plus this one is being compared in my mind to a stock and worn out engine that made very little power. due to low compression and terrible stock carb. This one has a Caravan head and a Weber carb plus a recent rebuild. BTW I hate the toilet bowl noise of the Weber- i'm ordering a Samurai adapter to try mating up the original air cleaner in hopes of reducing that. I tried making a video today but you couldn't hear anything in it, you really would have to see this to understand me- maybe there is nothing there but I sure want to know before I damage this engine with a 2200 mile trip out to Los Angeles.
11-16-2017, 12:21 PM
2nup350

Update- I just noticed my carb is a weber 27-28. Like for a 1600 VW. I wonder if this is going to work out or am I going to need a larger carb. it seems to run well and it might get better mileage with this setup but i'm certainly sacrificing power.
this might be the cause of my rough running?
11-16-2017, 01:07 PM
geezer101

That carb is strangling the engine worse than the 23/35DIDTA Mikuni. With a 32/36 Weber carb you will get everything - improved MPG over the Mikuni (unless you're lead-foot Larry), improved HP and torque and an improvement in highway cruising speeds after re-tuning the ignition. The 2.6 would've been trying to turn that tiny carb inside out!
11-17-2017, 06:04 AM
2nup350

Quote:

Originally Posted by 2nup350

Update- I just noticed my carb is a weber 27-28. Like for a 1600 VW. I wonder if this is going to work out or am I going to need a larger carb. it seems to run well and it might get better mileage with this setup but i'm certainly sacrificing power.
this might be the cause of my rough running?

FURTHER UPDATE
I pulled the carb and measured it-it's a 32/36. the number in the side of the carb referred to the original casting, not the machined final size. so I'm not going to buy a carb, but I'm back to square one with the tune. I had a Toyota truck enthusiast look at it and he said it runs better than his 20r, so he's no help. I'm starting to suspect this is just the way this engine runs.
11-17-2017, 05:27 PM
ragragtimetime

1 Attachment(s)

the red 86 4wd Attachment 19842runs like you have described....feels like you are in a helicopter ready for takeoff at slow speed low rpm...yet when on the highway its not noticeable.:shrug: It has the 32/36 weber with stock air filter adapter.
11-17-2017, 06:52 PM
2nup350

What Adapter did you use? I ordered teh Samurai adapter and it is too tall for my air cleaner.

Quote:

Originally Posted by ragragtimetime

the red 86 4wd Attachment 19842runs like you have described....feels like you are in a helicopter ready for takeoff at slow speed low rpm...yet when on the highway its not noticeable.:shrug: It has the 32/36 weber with stock air filter adapter.
11-17-2017, 07:22 PM
geezer101

Quote:

Originally Posted by 2nup350

FURTHER UPDATE
I pulled the carb and measured it-it's a 32/36. the number in the side of the carb referred to the original casting, not the machined final size. so I'm not going to buy a carb, but I'm back to square one with the tune. I had a Toyota truck enthusiast look at it and he said it runs better than his 20r, so he's no help. I'm starting to suspect this is just the way this engine runs.

You can give Toyota kudos for reliability, but the Mitsubishi trucks made more power. Back when they raced these things in their own class, anyone who used a D-50 had their trucks nerfed with an extra 150 lbs of ballast to make the overall class more competitive...
Bear in mind that the Weber has a bigger CFM than the Mikuni - it will sacrifice some low down torque for more midrange to top end power. You can reclaim some of that torque by lengthening the intake ducting. Other option is using headers.
11-18-2017, 04:46 AM
ragragtimetime

Quote:

Originally Posted by 2nup350

What Adapter did you use? I ordered teh Samurai adapter and it is too tall for my air cleaner.

K&N 85-1061 from a forum member

https://www.ebay.com/sch/i.html?_fro...-1061&_sacat=0

it does require cutting of stock base
11-20-2017, 05:23 AM
Old Boy

Is it possible that the timing belt is off a half tooth or so