CIS engine compression test rant

[dtw]

Just a need to blow off steam, here - I find it damned near impossible to do a compression test on the 4/5/6 bank on a CIS engine. Especially with an AC compressor! I'm sitting here with forearms scratched all to hell and gone from twisting and squirming all around the CIS plumbing all evening. It is really hard for me to thread the tester into the spark plug holes on the right bank, especially with the ancillaries in the way.

The left bank took me all of 10 minutes. Zooooom.

OK, rant over. I'm off to find a tasty beverage...

[diverdan]

Ouch! I've go an ordinary compression tester from the cheapie auto parts store that works so easily. I think it is because the fitting is on an approximately 12 inch long piece of hose with a quick connect to the dial. Its far easier to do than plug r and r. Agree on that dang a.c. compressor. I really ought to remove it and box it should I ever sell the car.

Good luck.

Diverdan

[john walker's workshop]

you take off the compressor by removing 3 bolts and set it on a folded blanket on the RR fender. takes 3 minutes, at least with the later setup. the early ones with the bolts under the compressor take 10 minutes.

[175mph951]

unbolt the compressor as said before....but also you should do a leakdown instead of a compression test....much more accurate and gives you a better idea of whats wrong if anything

[kodioneill]

try one of these.

leak down gauge. Simply insert this unique tool into the cylinder head and attach your gauge. Precisely machined from high quality stainless steel.

STOMSKI-SR031

Stomski Racing Leakdown/Compression Gauge Adapter, 14mm, each, 911 (1965-98) [Photo]
$55.00

pelican parts baby!!!

[dtw]

I was envisioning something like that Stomski tool last night. Figures that somebody already makes it.

John, yeah, I know the compressor is easy to remove - strangely enough, it was cylinder #5 that gave me the most trouble. Ended up with a fairly elaborate but effective way to get it installed. The 10:30pm, freezing my arse off, DIY version of the Stomski tool, but it worked.

175 - I usually do both tests together (if the compression test suggests leakdown). My compressor is down right now, unfortunately.

[nocarrier]

Here is a quick solution I came up with to help thread the compression test hose down inside the hole.

It's just a 5.5" scrap piece of copper pipe that I formed around the test hose with a small hammer.

While it's not the prettiest tool you have ever seen; it helps tremendously.

Just remember to bevel the other end of the pipe to prevent the hose from chaffing.

[nocarrier]