85 hp Chrysler

[Doodlemen]

I have an 1982 85hp Chrysler was running great 0-40 right now. Now I can only get 3500 rpm out of it. Revs good in neutral not under load. I thought plugs were fouled. No difference with new ones

 

[Nordin]

Check compression and spark at all 3 cylinders.

 

[Doodlemen]

Thank you for you're response. Will check compression today is 135-150 good

 

[jerryjerry05]

The actual # can vary with the gauge.
You looking for 145-150
Even results like all 3 at 100 or all at 145
Any big difference can show a problem.
Harbor Freight gauges

 

[Doodlemen]

Could carbon build up cause this

 

[jerryjerry05]

Yes it can.
But usually carbon build up is a slow progress.
Sudden loss is something like a coil, pack, trigger lead, head gasket, clogged carb etc.

Do the tests and post the results.

outboardignitiondotcom has test procedures for the electrical system.
The top 4 posts here cover a lot of things that can help. Read them.

 

[Doodlemen]

Beautiful blue spark all three cylinders. Ran the compression test cylinders two and three were 140 right on the nose and cylinder one a big fat goose egg

 

[Tassie 1]

Bugger.

 

[Doodlemen]

Took the head off and found number one pitted and damaged. Any links to help in the repair process would be greatly appreciated

 

[jerryjerry05]

These are fairly easy to rebuild.
Check the cyl. walls for scoring.
If it's deep enough to catch a fingernail, it needs a bore job.
Find a machine shop in your area(where's that?) that does outboard blocks?? lots won't touch them.
They can tell you how far they should be bored out.
Usually .020 is sufficient. Past .040 is probably too far.
Then you'd be getting into rejetting.
The parts are available.
Without the right tools, the pistons need to be aftermarket, Wiseco is the best bet.

 

[Doodlemen]

Thanks a bunch. I can barely get my finger nail into the scoring Will that affect my compression ratio between the three cylinders if I have it boared out the 30 or 20 over.

 

[Doodlemen]

I live in Eau Claire, WI

 

[jerryjerry05]

Keep it at .020
The comp shouldn't change much if at all.

I've rebuilt a bunch of 85's and 125's and changed just one piston.
I know one guy here is still running after 7-8 years.