1982 BJ40 with a “B” engine and who knows how many miles. I’m finally to the point in my restoration where I can drive it daily but I knew that the engine was an unknown quantity since we didn’t have time to rebuild it during the frame off restoration process before I imported it to the US. Driving the other day I noticed this noise on startup. I also noticed a bit more black smoke than usual. The oil pressure has always been low (15 - 20psi when warm) and compression on all four cylinders was 385 if I remember correctly from when I checked a year ago (probably 200 miles ago since it spent most of that year in the shop waiting to be worked on). This noise seems to be coming from the vicinity of the timing cover. I’m mechanically inclined, but this is beyond my abilities to diagnose. I do notice that the crankshaft pulley is vibrating and that made me think that it could be a bearing but I would appreciate any expert advice if you could take a look at these videos.
Help identifying this noise. (1 Viewer)
- Thread starter brianblack138
- Start date
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The first thing that comes to my mind is the oil pump - which on my "B" engine (1978) is driven directly by the crank - and resides behind the timing cover. Since the oil pressure seems to be fairly low, even though this is normal when the engine is warm. My engine produces about 100 psi on cold startup but soon stabilizes around 15-20 at idle when warm.
One thing you mentioned that is of more concern is the increase in black smoke ... this leads me to speculate on the condition of the valves and their adjustments. A faulty valve could cause black smoke. In fact so could worn rings ... oh man, these are old first generation engines ... and stuff does wear out eventually.
The vibration of the crankshaft pulley suggests a bearing issue ... which is consistent with a problem with the oil pump ...
Anyway, these are just my thoughts, and there are many more experts out there that have better informed guesses than mine. Good Luck !
One thing you mentioned that is of more concern is the increase in black smoke ... this leads me to speculate on the condition of the valves and their adjustments. A faulty valve could cause black smoke. In fact so could worn rings ... oh man, these are old first generation engines ... and stuff does wear out eventually.
The vibration of the crankshaft pulley suggests a bearing issue ... which is consistent with a problem with the oil pump ...
Anyway, these are just my thoughts, and there are many more experts out there that have better informed guesses than mine. Good Luck !
- Thread starter
- #3
Thank you,
these are all great places to start. I originally had planned to have the engine fully rebuilt while it was out of the vehicle, but ran into time constraints because I needed the vehicle put back together and able to drive in order to export it from Colombia and import it to the US. I knew that the engine was a ticking time bomb and knew that installing the turbo likely shortened the fuse. I had the inline injection pump and all injectors rebuilt this past fall and winter but didn’t touch the oil pump or valves. The diesel mechanic who was working on it did great work but was swamped with more business than he could handle, was unable to say “no” and was trying to get out of the business. The combination of these factors means that I’m in the market for a new mechanic.
- Thread starter
- #4
I took the plunge and ordered the B engine rebuild kit from SOR. I found a diesel shop nearby where one of the mechanics has worked on these engines before in forklifts and he will start the rebuild on June 22nd. Hopefully the crankshaft is still in good condition and I won’t need to buy anything beyond the rebuild kit. It’s definitely not the best way to do it (it would have been nice if they had rebuild the engine while it was out of the truck from November 2018 until October 2019) but oftentimes in Colombia things don’t go as planned. At least it should be good for another 40 years after this rebuild.
Could you remove all the belt and run the engine without the auxiallarie (alt, steering pump, water pump, ac?) For 30 sec ( no cooling) and see if the sound still there. The only ball bearing in the timing cover is the injection pump gear bearing which receive oil (could be but I doubt, it would have start a long time ago) take a long screw driver (NO BELT) touching the engine and earmuff you could listen and trace the source of that sound.
- Thread starter
- #6
I bought a stethoscope today to try this. I didn’t think about removing the belts but I could do that. I’ll start out with the belts on and then take one off at a time to see if the noise stops. Then I’ll run it with no belts for a few seconds and see what I hear.
