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kung fu jesus
02-17-2012, 08:27 PM
I did a compression and leak down test on my engine today. Warmed up the engine, pulled the fuel relay, pulled the spark plugs. WOT.

#1: 205
#2: 198
#3: 200
#4: 205

The head has been shaved and p&p'd

The leakdown:

#1: 4%
#2: 26%
#3: 6%
#4: 4%

I scoped the the combustion chambers with a snap-on camera/monitor. I could clearly see the cross-hatching on all four cylinders. There was minimal carbon build up. #2 leakdown was coming out the valve.

Block has 163,000 miles on it, the head about 70k miles. Wishing I had replaced the valves when I did the headwork instead of refurbing the old ones.

What are "normal" compression results for a 1.6 b6?

Itsaparty
02-18-2012, 12:14 AM
Hello Jesus, manuals say compression for brand new motors is 190 all across.
In the 200's due to shave?

Maikeru
02-18-2012, 12:21 AM
In the 200's due to shave?

Most likely. Your motor is healthier than my B6.

kung fu jesus
02-18-2012, 03:27 AM
Thanks for the numbers!

Yes, the shave will raise the results.

DaveL
02-18-2012, 02:30 PM
Did you use the HF leakdown tester? If so I would call those numbers inconclusive. Why do I say that? I was sucked in by price also. A good rester with gauges that top out at 200psi will give a much more accurate reading.

kung fu jesus
02-18-2012, 03:38 PM
HF? Can you be more specific, please?

I used the dual gauge manifold at the shop. Set the air pressure to 50 on the manifold.

I was doing a 1.6 comparo with Vega (Sonny) and Satasii (John).

If all three cars were turds, mine was better because it had corn in it.

AARP
02-18-2012, 05:40 PM
HF? Can you be more specific, please?


Harbor Freight.

kung fu jesus
02-18-2012, 06:18 PM
Nope, not a HF manifold. I rechecked the compression today with another gauge, my own, and the numbers were within 5 psi of the first readings with the engine pretty heat soaked.

Itsaparty
02-19-2012, 01:15 PM
what are you plans?
re lap them and new valve seals?
or new everything?

i've got a couple b6 heads sitting around.

Satisaii
02-19-2012, 02:21 PM
The compression tester is a Snap-On. I think the leak down is OTC, and it is new.

kung fu jesus
02-19-2012, 10:13 PM
Not sure on the plans. Would like to get new valves/springs/retainers/keepers and seals, but the car runs fine for now.

Darthteddy
02-29-2012, 08:26 PM
9000 rpm motor !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

joe morreale
03-01-2012, 11:19 AM
If the car seems to run ok then I would just drive the hell out of it. If your leaky valve gets worse it'll probably start missing or running rough. If that time comes then it's time to take the head off again.

kung fu jesus
03-01-2012, 11:27 AM
yes, that is the plan. I get a miss sometimes, at low RPMs under load, but nothing that terrible.

cjsafski
03-01-2012, 04:39 PM
The compression seems fine. Leakdown numbers are ok except for that odd 26% on number two. Since the compression on that cylinder is ok I bet the tester didn't seat right. Did you stick your ear neat the exhaust, tb or oil cap when doing the leakdown? That usually tells where any problem would be. Personally I wouldn't worry about the numbers. Have you checked the gap on your plugs recently? That may be a source of the miss you describe.

bokehmon
03-08-2012, 04:13 AM
yes, that is the plan. I get a miss sometimes, at low RPMs under load, but nothing that terrible.

I used to get that, until I changed out my coilpacks.

kung fu jesus
03-08-2012, 10:37 AM
Chris, that is a distinct possibility, but compression is cumulative.

Jay, that's what I was thinking. I have a spare set I may swap in Saturday.