Pulled the plugs today..., Compression check, got confused... |
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Pulled the plugs today..., Compression check, got confused... |
blk'72 |
Apr 10 2005, 12:39 AM
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#1
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Member Group: Members Posts: 83 Joined: 2-November 04 From: Pleasanton, CA Member No.: 3,053 |
Hey all...
I had a exhaust leak coming from the right heads/exhaust headers... SO a I wanted to see if that was just a leak, and if internals got damaged? Pulled out the headers, and exhaust, and headers are all black and greasy! Plugs out and they look ok, just a little black but nothign crazy(NO CRACKS< NOTHING JAMMED). Now here's where I need help.... How do you do a damn compression check! I have the tester, and what ZzE fuck de bordel de merde should I do whith it? Anybody uses them who can help? Thanks a bunch.... My offer for the east bay peeps is still good....anybody want to come over to pleasanton tomorrow after 4 is welcome to....Hopeyard and corte sierra. GImme a call, we can work on cars together 925.989.7345 Fum times (IMG:http://www.914world.com/bbs2/html/emoticons/beerchug.gif) R. |
john rogers |
Apr 10 2005, 12:47 AM
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#2
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Senior Member Group: Members Posts: 1,525 Joined: 4-March 03 From: Chula Vista CA Member No.: 391 |
The engine should be warm to do an accurate test but if it is cold it will be a little low since the rings will not be seated as good as could be. To do one, pull the plugs, lock open the throttle wide, put a charger on the batt so it is at full power the put the compression tester in #1. Have someone crank the engine and watch the gauge jump up. It is important how fast it rises and it should get close to full pressure in just a few cranks then a few more to top off. Bleed off pressure and repeat for #2, 3 and 4. Compare the rate of rise and total pressure and they should all be close. If you have a radical cam with lots of overlap then the rise will be slower than for a stock type of cam shaft. Good luck
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GWN7 |
Apr 10 2005, 01:43 AM
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#3
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King of Road Trips Group: Members Posts: 6,280 Joined: 31-December 02 From: Winnipeg, MB, Canada Member No.: 56 Region Association: Northstar Region |
Don't forget to pull the coil wire so the engine dosen't start on the other 3 cyl.
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DBCooper |
Apr 10 2005, 05:49 AM
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#4
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14's in the 13's with ATTITUDE Group: Members Posts: 3,079 Joined: 25-August 04 From: Dazed and Confused Member No.: 2,618 Region Association: Northern California |
You want all the plugs out when you do the tests. It's good practice to give each cylinder a squirt of oil through the spark plug hole before cranking. That will seal the rings and the difference between readings for a hot and cold engine won't be much. You're cranking with no compression, so I've never needed a charger unless the battery was bad anyway.
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GWN7 |
Apr 10 2005, 08:29 AM
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#5
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King of Road Trips Group: Members Posts: 6,280 Joined: 31-December 02 From: Winnipeg, MB, Canada Member No.: 56 Region Association: Northstar Region |
Here is a good article on compression, leak down tests, wet and dry testing and Interpreting The Results of these tests.
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blk'72 |
Apr 10 2005, 07:48 PM
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#6
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Member Group: Members Posts: 83 Joined: 2-November 04 From: Pleasanton, CA Member No.: 3,053 |
AllrightTTTT!!!! (IMG:http://www.914world.com/bbs2/html/emoticons/smilie_pokal.gif)
Thnks you guys! Now I just need to get back down to the garage ...( I just got out of the shower and covered myself with some of that magic orange paste grease remover....) I was working on the exhaust system... Maybe you can help me....the 4 studs holding the exhaust manifold to the heads, were fixed with (heli?)coils ...and only one stud was still in there holding the whole exhaust system, explains the exhaust leak I had... The only stud I have to rely on is this one and iti s 10mn on one sid plus the spring, and 8mn on the other side??!?!?! Is this what I need to replace on the other 3?Is this a factory stud? I need help? Someone? R. |
SGB |
Apr 10 2005, 07:59 PM
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#7
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just visiting Group: Members Posts: 4,086 Joined: 8-March 03 From: Huntsville, AL Member No.: 404 Region Association: South East States |
Pretty sure the studs are 8 mm on both ends. Yes, the 10 mm heli-coil didn't stay in the head. Happened to me last time I removed heat exchangers, also. I bought a tap set and ran them all out to 10mm, then bought studs that were 8/10. That may be "bad", but I cant think of why this isn't as good as heli-coils.....
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blk'72 |
Apr 10 2005, 09:41 PM
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#8
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Member Group: Members Posts: 83 Joined: 2-November 04 From: Pleasanton, CA Member No.: 3,053 |
thanks scott...
I just want to add this....do VW shops guys know what they are doing/saying when it comes down to our cars???? I am asking this because I went down to this one VW place on the bay area which I will not name, and the guys sold me WRONG eeeeeeeverything!!!! Common or not? Whtvr (IMG:http://www.914world.com/bbs2/html/emoticons/headbang.gif) Anybody in pleasanton up to meet? Still thinking about ya Paul, if you red this (IMG:http://www.914world.com/bbs2/html/emoticons/pray.gif) R. |
nebreitling |
Apr 10 2005, 09:46 PM
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#9
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Member Emeritus Group: Members Posts: 3,314 Joined: 26-March 03 From: San Francisco Member No.: 478 |
i don't trust bug-shops for advice (hell no), but i'll go there looking for specific parts.
helicoils suck, IMHO. but time-serts are $$$. tapping is okay, just make sure you do it straight. Loctite/JB-weld the hell out of the thing, too. and wear safety glasses (ask me how i know). n |
blk'72 |
Apr 10 2005, 09:53 PM
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#10
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Member Group: Members Posts: 83 Joined: 2-November 04 From: Pleasanton, CA Member No.: 3,053 |
-"SooOOo , how do you know?...." (IMG:http://www.914world.com/bbs2/html/emoticons/mueba.gif)
I kindda found out too earlier, just some rust and grease getting n my eyes....NNNniiIIIIcEe! (IMG:http://www.914world.com/bbs2/html/emoticons/mad.gif) |
nebreitling |
Apr 10 2005, 10:43 PM
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#11
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Member Emeritus Group: Members Posts: 3,314 Joined: 26-March 03 From: San Francisco Member No.: 478 |
at least it wasn't metal shavings...
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blk'72 |
Apr 10 2005, 11:54 PM
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#12
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Member Group: Members Posts: 83 Joined: 2-November 04 From: Pleasanton, CA Member No.: 3,053 |
ouaaaaaaaaach!
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