Update Winter Project

Jan Rella

New Member
Hi Everyone

New here and wanted to share what I picked up today! 1974 (or 75) ST90, 3500 miles non runner. Good compression but no spark I’m told. It’s still in my truck! I’ll keep posting and I’m sure will have a million questions!
Thanks
Jan in NJ
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Jan Rella

New Member
UPDATE:

Working thru the no spark issue. Found worn points...awaiting replacements.

More troubling finding was 60psi compression. Shot some oil into the cylinder and still 60 psi. I opened the intake valve inspection port and everything looks good inside. I'm planning on doing a valve adjustment and checking the timing when I get the points. Will it start with only 60 psi of compression?

It has 3600 miles on it. I changed the oil and it looked good...dark but good.

Am I wasting my time? Should I just commence the teardown? I was going to try to get it running before starting a freshening up.

Thanks for the input!

Best

Jan
 

DAX-IT!!!

Member
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It might just be smoking a lot because it hasn't run for long, long time and because of the oil you put in the barrel. Also, there may be years of crud in the exhaust thats being burnt off.

I bought an ST 90 that had laid in an out-house for years. I firstly changed the oil, (that smelt like parafin and ran like treacle) cleaned out the tank (as best as I could) of the caramelised petrol residue, cleaned the carb and fuel lines, freed the timing advance weights, cleaned the points, checked timing, checked/set the valve clearence gaps, put some fresh fuel in and it started - it still smoked !!! :eek:

Check all the obvious things first, give it a run round the block and see if the smoking stops/clears before heading out on the stripping the engine down road - it might just save you a lot of unecessary grief !! :) Then you can use all that extra time saved making it look great !! ;)

I've put a picture of mine up to give you an idea of what it was like.

I'm now rebuilding it so will post more pics as and when. Hope you get it going and looking great :monkey: - best regards !!!
 
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Jan Rella

New Member
Thanks for the reply Dax!

I'm soaking the chamber in Marvel Mystery oil now. I'll fire it back up and see how it goes!

Jan
 

Jan Rella

New Member
Dax
I'm zero percent sure about the rings! I figured that it's been laying around so some penetrating oil won't hurt. If it doesn't clear up then it's most likely a valve job and new rings while she's opened up.
Cheers!
Jan
 

red69

Well-Known Member
My S90 had some smoke for a couple of miles after 30 years being dorment. Cleared up and runs fine with no smoke now.
 
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