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ea81 asv, ticking, and compression

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Long post.. Trying to give as much info as I can...

 

Well, I got a Weber for my Brat (1983 3AT Hydro) and she's running well after about 1,000 miles (minus the choke not working) plus, I'm getting 22-24 MPG with a 4WD 3AT, while I WAS getting around 13-15 with the Hitrashi :lol:

 

Now, I have another couple issues I have. I blocked off the ASV pipe on the driver's side with a quarter. However, I have a canister (what IS that thing? ASV right?) on the passenger's side that has a pipe connected to the side of the head. All I did was stick a huge bolt in the vacuum line coming from the canister when I put the Weber on. Is this suitable, or is there a more proper way to block off that canister, or do I actually plug it in somewhere??? Not trying to roast my motor...

 

Which leads me to the next issue... Idle is dead on, but still kinda shakes... I'm getting a horrible ticking noise from what seems to be the exhaust. The ticking increases with RPMs until about three grand, and usually unheard on the highway even without a stereo. I'm guaranteeing I have an exhaust leak, probably on both sides of the y-pipe before the cat... As for oil pressure, it sits on around 50-60 PSI on the highway and I'd say 40-50 in the city. Drops to maybe around 25 when it's idling warm. Leaks from a few spots, I'm sure if I resealed everything the pressure would be better than it is. Anyhow, getting rid of that ticking would be superb :grin:

 

And last but not least... I threw a compression tester on the Brat... compression was around 110-120 in cylinders 1 and 4... and around 140-150 in the other two. Like valves are stuck open? Or could it be something else? Maybe I did the test wrong? I did use one of those cheapy old-school testers that you just stick in the plug hole... no screw-on attachment.

 

Nonetheless it drives well and I'm making great progress getting her back together :banana:

Most of the EA81's that didn't have feedback carbs had ASV's on both sides. Some are vacuum operated and some are not. Cut the steel tube about 2" from where it threads into the spacer under the head - put a quarter down in the bottom of the threaded port on the spacer and thread the 2" section of the tube back one. Eliminate anything else that was connected to the tube. Do the same for both sides.

 

The low compression is probably exhaust valve seats. To fix you would have to pull the heads.

 

The ticking could be exhaust leaks or it could be lifters. The lifters are accesible only with the oil pan removed and the push-rods loosened. If they are ticking it likely means they are dirty or worn - you have good solid oil pressure so that's not the problem. Try replacing one quart of oil with ATF for a while.

 

The shaking at idle is probably a vacuum leak or a lean miss. Check for vacuum leaks and check how hot your spark looks and regap your plugs if you haven't done it recently.

 

GD

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