Can our engines develop morning sickness? |
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Can our engines develop morning sickness? |
andreic |
Oct 16 2018, 09:42 AM
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#1
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Member Group: Members Posts: 172 Joined: 21-December 15 From: Madison, WI Member No.: 19,479 Region Association: Upper MidWest |
My 1972 914 1.7L suffers from what I call "morning sickness" -- the first time I start the car on any given day it runs like crap for the first 10-15 minutes. Skipping, won't rev up above 1000 rpm, very low idle, stumbles frequently, sometimes backfires. Also makes some strange noise around 2000 rpm, like a very loud rattle, especially when letting off the throttle.
After 10 minutes all is good, running well for the rest of the day. The compressions, which I have only checked with the engine hot, are uniformly 120-125 PSI. I come from an aviation background, and aircooled airplane engines are known to have this kind of morning sickness at around 1000-1200 hours since overhaul. The cause is carbon deposits in the valve guides, which make the valves stick when the engine is cold. After warming up, the guides expand from the heat, and the valves do not stick any more. The solution is reaming the guides, which can be done with the cylinders in place (for airplane engines). Is this something that can happen to our type IV's? Could this explain the problems I am having? What is the cure, short of taking the engine out and sending the heads to a shop? Thanks all. |
Rand |
Oct 16 2018, 01:53 PM
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#2
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Cross Member Group: Members Posts: 7,409 Joined: 8-February 05 From: OR Member No.: 3,573 Region Association: None |
QUOTE But at least carbs dont have gremlins in em , what you see is what you get Djet repair list : a wegeee board , a witchdoctor, a bottle of whiskey, a crystal ball and a magic 8 ball . See where im going with this. Please don't fall for that. Carbs have as many gremlins as FI. If you thing you need a wee-gee board to fix something it only exposes that you don't understand it. If you think carbs are superior to FI, you need to go back to your witch doctor. If you have djet, there are resources to help you work through it methodically without turning to voodoo. Oof. |
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