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Old 10-16-2017, 04:07 AM
Ian47 Ian47 is offline
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Default Bad starting hot

I have D24T fitted in my boat, I have just replaced the timing belts and timed the engine to .85. She starts perfect and runs fine, however when I stop her and immediatly try to restart her, she won't start. If I leave her for a bit then try her she eventually starts. I read somewhere a long time ago that this can happen if she is too far retarded. I am not confident that the cold start was fully disconnected as it is a bit rusty, so the dial gauge reading may not be accurate, can anyone adsvise me?
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Old 10-16-2017, 04:46 AM
RedArrow RedArrow is offline
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Im not sure you have the same issue but it may help to know:
When my glow plugs were tiring and slowly going bad, I had similar experience. Disconnected that brown wire that runs 12v to the temp sensor at the back of the head near the pump, it solved the problem (system thinks your engine is dead cold and provides longer glowtime) till i got new glowplugs in.

Ohhh but that time i had hard starting ALSO when engine was cold. You dont have that so it must be something else.
I read it here that harder warm starts *may* indicate "lower than optimal" compression.But again,
If you just did the belts and timing recently then maybe rechecking the timing would be good. (Hopefully you never had hard warm starts before )

Last edited by RedArrow; 10-16-2017 at 04:50 AM.
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Old 10-16-2017, 08:07 AM
v8volvo v8volvo is offline
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Timing is a good place to start. If the cold start lever was not fully retracted into the "warm" position (all the way to its stop with noticeable free motion in the lever) when you set the timing, that would result in a false high reading on the dial relative to where the static timing is actually set. If in doubt you can check it fairly easily, either get the cold start cable fully released or if the cold start thermostat is functional, just check the timing when the engine is warm and the cable has retracted automatically.

Other common remedy for slow starting is incorrect valve lash, good to check this as well if you are not sure.

Otherwise, compression would be your next area to investigate, but for it to be unable to start at all when warm, the compression would need to be so poor that you would probably see other symptoms as well, eg high oil use, blowby and related oil leaks, smoke, difficult starting when cold, etc. If you are not observing these then the bottom end is probably OK, but if the above checks don't get you anywhere, then a compression test would be useful information.

Final critical area for good starting is cranking speed. Are the battery/cables/starter all healthy? Sometimes if the starter is slow, the glow plugs causing a quick start masks it when cold but it becomes an issue when warm.
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Old 10-16-2017, 01:38 PM
Ian47 Ian47 is offline
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Thank you for that information, I hadn't thought about checking timing when warm, the engine doesn't use any oil, doesn't smoke and there isn't any blow by, so I think the engine is OK.
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