3b once agian loss of power

Joined
Feb 4, 2009
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sunshine coast
the engine is shaking like its running on 3 cylinders
it has a bad clacking sound from in the engine.

I've checked:

compression, all good 420 or higher
pre-cups are still in
cracked open all the injectors, one at a time, to see if the engine wound sound different from cylinder to cylinder. all good there. fuel there and all cylinders firing.

what would cause so much loss of power, clacking and shacking???

thanks guys!
 
Joined
Aug 26, 2007
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france
A loud knocking noise can come from a seized injector or injectors .I often have this problem with old boat engines with water in the fuel you doent need much!
 
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Feb 4, 2009
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sunshine coast
oil pressure hasn't dropped at all, i dont have a mechanical gauge but the stocker one is alright. it reads 2/3. i've never had a cruiser with this good of oil pressure.
 
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Feb 4, 2009
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sunshine coast
the only thing i've noticed that doesnt seen right is the amount of wobble the crank pulley has. could this indicate a forward bearing failure???
 
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sunshine coast
and i've rechecked the injectors, idle drops the same amount when you crack each injector. woun't this indicate that they were working????
 
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Dec 11, 2008
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Whidbey Island, WA
and i've rechecked the injectors, idle drops the same amount when you crack each injector. woun't this indicate that they were working????

Yes, that does indicate the injectors are working. But make sure to crack the injector far enough for the cylinder to stop firing. Then compare each one.

If it's doing it all the time now, you might consider dropping the pan and taking a look at the bottom end before things get worse.

If the crank pulley is loose tighten it back up.

Let us know what you find, best of luck hope it's something simple

Tony
 
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Jun 13, 2005
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Centre of the universe
Pull the intake off of the throttle plate and put your hand close... not too close as it can suck pretty hard. Is it a constant pull of air, or is there a "pulse" of air that is pushing out? When my head gasket went it did that. It could also be an intake valve if it does that too I guess.

Check your injection timing as really advanced timing can make some nasty sounds. When I say check it I mean are the lines on the pump pretty close.

And just grasping at straws, but you could use a dial guage and rotate the engine by hand (easier with the glow plugs out) and measure how much your valves are opening. Who knows, maybe one of your cam lobes is all round or something.

I hope its just the pulley itself thats loose. If mine was moving all around Id be changing my huggies.


g
 
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Joined
Sep 3, 2007
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New Zealand
the only thing i've noticed that doesnt seen right is the amount of wobble the crank pulley has. could this indicate a forward bearing failure???

Don't worry about anything else till you get to the bottom of this Slim!

There should never be any wobble .... And if the pulley has come loose on the crankshaft you'll need to remove it completely to check how much damage has been done (rather than just attempt to secure it by tightening the securing bolt).

Good luck...

:cheers:

PS. I wouldn't advise continuing to drive it in its current state.
 
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Sep 28, 2002
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Kamloops, BC Canada
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Don't worry about anything else till you get to the bottom of this Slim!

There should never be any wobble .... And if the pulley has come loose on the crankshaft you'll need to remove it completely to check how much damage has been done (rather than just attempt to secure it by tightening the securing bolt).

Good luck...

:cheers:

PS. I wouldn't advise continuing to drive it in its current state.


^^^^ This is the first place to look ^^^

The next one would be at the valve train. The 3B, in some cases, has a tendency to turn the cam bearings and the top end loses lubrication. The rockers then wear very, very quickly and you will get terrible performance and lots of noise.

If you remove the valve cover and idle the engine, and there is no oil coming out of the oil holes on the rockers themselves, you have found your answer. You may also find grey sludge from the iron of the rockers wearing on the rocker shaft. The valves will be quite loose as well.

~John
 

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