MD5A wont tick over

[tabnabtoo]

Have already posted this on the main forum,but new to this and didn't realise there was a diesel engine forum.So here goes again.
My volvo MD5A will not idle.Have set up the govenor/throttle linkage as per the manual.Replaced the injector pump and checked the timing.The fuel and air filters are ok.Today I checked the valve clearances and still it will not run below about 1000 RPM. Below this it just slowly dies. Might try the injector next although a mechanic friend of mine said this was unlikely to be the cause of the problem.Any other suggestions very welcome. Thanks in anticipation. By the way, when I googled MD5A there was a link to utube with a video of an MD5A ticking over!!Why would anyone want to watch a diesel engine ticking over.Get a life! Perhaps it was put on there to taunt me!!?

[shogan50]

$450 Injector rebuild on my 7a made very little difference and they were supposedly toast. Everything else in working order, the governor should increase fuel delivery to regulate RPM. Are there any other symptoms - difficult to start, smoke?

[jrd22]

shogan is on the right track asking about other symptoms. How does it start in cold weather, does it smoke and if so what color. Does it smoke when it's running and warm, use oil? Have you checked your fuel pump, maybe at low speed it's not delivering enough fuel to the inj. pump?

[tabnabtoo]

Thanks guys, the engine starts well with no smoke when it's warmed up.The fuel pump doesn't really come into it as the tank is above the engine and I was able to bleed it by gravity alone when I changed the injector pump the other day.I,ll get the injector checked out this week and see if it makes any difference-- it's straw clutching time!

[tabnabtoo]

Solved the problem!!!! It was the governor springs.I had to take the engine out and remove the governor.I experimented a couple of times by putting it in my friends lathe.The governor turns at the same speed as the engine.By fitting much weaker inner springs I got it working at the right speed.The springs fitted were much too strong and the governor didn't work until about 900rpm or more. The engine now starts better[although I can't think why] and ticks over as it should. Result!!.