Can Hard Downshift Mess With Engine
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Compression check, leakdown check, think about pulling the head off to check for bent valves or pushrods. Look for broken valvesprings, cracked top caps, and if you have a borescope look for signs of piston to valve collisions.
Any damage is likely to be internal or mechanical - faffing about with plug wires is like putting up an umbrella in a tornado.
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I always thought old cars were expensive......then I got an ex-wife
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I believe, upon reflection, that I went 4th to 1st.
The engine felt a little different, but I was a little shook up AND THEN THE FRONT WHEEL FELL OFF (loose wheel nuts from shop).
The shop repaired the damage and didn't note any engine issues. And it seemed fine for a while and then it didn't.
It's going back to the shop as my mechanic skills (such as they aren't) are tapped out.
If it seemed OK at first, then not, then it may be an un-related issue. Maybe a loose wire or vacuum line or something as simple as the dashpot oil getting low. Let us know what the shop finds, though loose wheel nuts would make me dubious.
.
"Hang on a minute lads....I've got a great idea."
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I always thought old cars were expensive......then I got an ex-wife
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I believe, upon reflection, that I went 4th to 1st.
The engine felt a little different, but I was a little shook up AND THEN THE FRONT WHEEL FELL OFF (loose wheel nuts from shop).
The shop repaired the damage and didn't note any engine issues. And it seemed fine for a while and then it didn't.
It's going back to the shop as my mechanic skills (such as they aren't) are tapped out.
I always thought old cars were expensive......then I got an ex-wife
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I'd start with a compression check to see that all valves are seating. That would almost rule out valve damage, though not necessarily a bent pushrod.
Next I would check static ignition timing WITHOUT ADJUSTING ANYTHING. That might indicate if the valve timing has been shifted. If your static timing was at say 8 deg BTDC and now shows something different, say 10 or 12, then you can suspect the valve timing has shifted. (Timing between the cam and distributor won't change. I'm thinking the cam timing would have jumped forward in this scenario.)
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A friend lent his UJ Mini out to another friends wife at a track day a few years ago, and she went third to second at flat chat - the engine has smoked like a battleship ever since and has precious little oil pressure. Something broke.
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I wasn't going really fast and the engine still runs, but almost like it is running on 3 cylinders, but not quite. No power.
I always thought old cars were expensive......then I got an ex-wife
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In my opinion it shouldn't alter timing, unless the timing chain has a lot of slack - enough to allow it to skip a tooth. It might happen if the crank was forced to change rpm instantly and the cam momentum jerked the chain, but I doubt it.
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Quick, and possibly a stupic question.
Can a hard downshift, say fourth to second, where the front wheels shutter cause a timing problem in the engine?
Let see if you think it can happen and we can go in to more detail.
Thanks!
Kevin
In Ottawa.....Canada, not Kansas
I always thought old cars were expensive......then I got an ex-wife