How to fix a vibrating engine

[ontherocks83]

Originally Posted by a64pilot

If it is a bad injector you may want to invest in a new one. Have your old one fixed and keep it as a spare. Injector problems are common enough to warrant having a spare in my opinion


Sent from my iPhone using Tapatalk

+1 I'm willing to bet that recommendation is from your aviation side. Fix it right the first time,........ but because we're talking about boats that can't fall out of the sky keep a good used spare just in case.

[DeepFrz]

If you don't know how long its been since the injectors were serviced take them all in for cleaning and adjustment.

[kungfoo]

Originally Posted by youngsalty

Thanks everybody.

After reading the post several times here is what I have gathered information wise. The leak filling the bilge from the shaft is its own problem, not related to the vibrating engine. The engine vibrating while idling has a good chance of being cause from a bad fuel injector or a slight chance from the rubber feet on the motor mount being worn out. I suppose first I will look at the rubber feet, easiest first and then try to find the bad injector next as mention how from above.

It might also be worth getting an optical tachometer and checking that your idle speed is circa 800. I had the same problem with my engine, where the idle speed was set too low, and it vibrated like crazy. You can get an optical tachometer for $10 off of Amazon: Amazon.com: AGPtek® Professional Digital Laser Photo Tachometer Non Contact RPM Tach: Automotive

[Cheechako]

Originally Posted by donradcliffe

Crack the nut on the injector input pipe (not the return pipe) to each injector in turn--if the engine slows/runs rougher, then its not that cylinder. If the engine stays the same, you have found your bad cylinder. The first and cheapest thing to do is to pull that injector and take it to an injector shop for testing/replacement.

yep, the engine should not be rough. If it doesn't smooth out when out of gear, then you have an engine issue. This is essentially a Perkins 4-108 right?

[youngsalty]

Alright, now I got it. Can't thank you guys enough sticking with this post and helping me out. I'll let you know how it goes in a couple of days. Good idea on fixing and keeping as a spare.

[youngsalty]

yes, it is exactly like the Perkins 4-108.

[SkiprJohn]

Engine mount test: Get into the engine compartment, put both your hands on the top of the engine and try to shake it back and forth. If it wobbles loosely that's your problem.

That's an easy one that you can do before the injector test.

Is your dripless shaft log one that will fail all at once and flood your boat?

[chris95040]

Keep us posted!

I have a Westerbeke 55B, 4-cylinder, based on an Isuzu block I think. She seriously shakes at what the tach claims is 750RPM, settles down to nothing at 1000RPM. Engine mounts look good and she's mounted low on the studs.

I've read other forums here and elsewhere that suggested increasing idle speed is the "fix", although that must certainly have an impact on transmission life.

I like the idea of using an infrared temperature gauge to look at the temperatures from cylinder to cylinder, neat!

[builder dan]

Engine mounts soften with age and use,As Skipper John said give it a good shake,They are usually fairly easy to replace.

[Rick01541]

I have a 1998 Westerbeke 55. Replaced the engine mounts and it runs smooth as silk.

[youngsalty]

Hi everybody,

So I loosen the nuts on all 4 fuel injectors and passed the test the same. I could not find a bad one. Surprising easy test with not much fuel shooting out.

So my next step is to see if the engine is idling to low in neutral. Is 600 RPMs what it should be when you first start your engine? Also I am going to give a better look at the motor mounts again. I did give it an oil change to check the oil for any antifreeze, the oil was clean.

One test at a time.

[Cheechako]

600 is pretty low, that may be your problem, at what rpm is it smooth?

[donradcliffe]

I'd bump the idle up to 800 rpm. Read the manual on how to do it, so you don't turn the anti-stall by mistake.

[SkiprJohn]

Originally Posted by donradcliffe

I'd bump the idle up to 800 rpm. Read the manual on how to do it, so you don't turn the anti-stall by mistake.

I second that motion. 600 is too low.