Valve lap adjustment results (1 Viewer)

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Mr Cimarron

DRIVE, BREAK, FIX, REPEAT
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Question for smarter people.
Yesterday I did a valve lap adjustment on my BJ40, B engine. They were adjusted while the engine was hot using the correct "hot" adjustment. Afterwards it seems I have a bit more RPM range but maybe its only in my head.
I am wondering what the typical things one might notice after adjustment on these old diesels.
 
The only difference Ive noticed was when the tolerance was too tight and I suspect they were allowing leakage. Although they are horribly underpowered, they are fairly forgiving performance wise when it comes to timing and poor injectors and stuff compared to DI.
 
If they were too tight then sure you would have felt a difference, but the drop in performance if they were too tight would have made it almost un drivebale. if they were too loose, then they would have to have been very loose ( wide gap) to have lost you performance and bloody noisy to boot.
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I hope MrC can take a joke
 
Good question John, diesels are noisy in themselves, in reality if they are out of adjustment enough in the " too much gap" direction then you are going to be buggering something else up before you realise that the performance has dropped off. Best to lift the cover find TDC and check, one should be able to wiggle all the wiggleable tappits slightly, but not mm's. Turn the engine 360 and the other 4 should now be able to be wiggeled. This is a good enough go/no go test and although the gap may not be correct, you should still be able to start and run without causing any damage.
 
My exhaust were a bit tight. If I was a smart person I would have taken a recording of before and after to see if there was a noticeable noise difference. Intake were probably close enough but I adjusted everything just to say I did. It literally was a 15 minute job. The hardest part was turning the crank pulley using a short 1/2" ratchet because my long one was hitting the radiator support rod. Even the short one was only getting one click due to hitting the radiator skid and fan shroud.
If I remember correctly valves 1,2,3,6 can be adjusted together and then 4,5,7,8 once engine is turned 360 degrees.
 

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