volvo 850 kicks back on hot start

[JimBee]

Starts right away when cold, or cooled somewhat for up to 1/2 hour after running.
But immediate start when hot or warm, engine kicks back, almost as if the timing is too advanced. Once started, the engine runs fine.

I worked a lot with small farm engines back in the day. If an engine preignited when you cranked it (pulled the rope, turned a crank handle), the engine would kick back. (Model T Fords apparently were infamous for dislocating thumbs if the spark lever was too advanced). My hot start issue seems like that.

Since cold start isn't a problem I don't suspect ignition parts, but ignition timing does seem to be an issue. I haven't changed the timing belt since maybe 20,000 miles and the problem hasn't occurred until recently, so I'm not sure what to suspect. I did upgrade the spark plug wires, that didn't change anything.

[volvolugnut]

I would also suspect a timing issue. Get out the timing light?
volvolugnut

[JimBee]

hmm timing light. I do have one...somewhere. I think my first cut on this will be to have a look at the topside belt pulleys to be sure their marks align with the notches in pulley cover. I'm pretty sure I reused the belt tensioner when I changed the belt. The mark alignments should confirm if it's correct.