Thread: scary compression readings
06-06-2010, 09:04 PM #1
scary compression readings
Well, I notice my ski over the last few days seemed to be dumping a bit more into the catch can. And also noticed a light white smoke that I haven't seen before! Ski seemed to be lacking that top end punch from a week ago also! Plugs were a bit wet also 170 hours on motor
Compression findings: cold engine, plugs in other cylinders, battery fully charged, Throttle held WOT!
Checked 3 different times with two separate gauges!
Ran second test later with fogging oil sprayed into cylinders
Looks as if I will be pulling a head soon and possibly more!
Last edited by Rendog; 06-06-2010 at 09:10 PM. Reason: more info
06-06-2010, 09:09 PM #2
06-06-2010, 09:10 PM #3
06-06-2010, 09:12 PM #4
You need to check your compression with a warm motor!
06-06-2010, 09:13 PM #5
alright, ill do it tomorrow after work and post readings
06-06-2010, 09:27 PM #6
What ski??? I have gotten anywhere from 120 - 150 psi compression on my RXP, depending on where cam timing is, whether there are spark plugs in other cylinders, etc, on a cold engine with a freshly charged battery. So hot or cold makes little difference, possibly 5 lbs difference on average ... so unfortunately your readings do sound scary. Pull the valve cover and take a close look at your valves for a start, and verify cam timing marks, etc.
06-06-2010, 09:28 PM #7
- Join Date
- Oct 2007
cold engine, plugs in other cylinders,
I know it makes a diff in 2 stroke engines but does it affect these 4 tec motors not having all other plugs in??
06-06-2010, 09:30 PM #8
It does ... I got 145 in all 3 with no spark plugs in, throttle held WOT. Put in 2 spark plugs, got 150 in each cylinder. Fresh battery, cold engine.
06-06-2010, 10:05 PM #9
2005 RXP I run the ski year round and know its just a matter of time before I need to change the valves anyway
06-06-2010, 10:31 PM #10
Really need to have the other 2 plugs in when doing compression readings. Charger on the battery also helps with consistancy.
Leakdown always tells the real story.
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