Couple of compression test questions
Thread Starter
Joined: Jan 2002
Posts: 4,069
Likes: 74
From: Casselberry FL
Couple of compression test questions I want to buy the parts to learn how to do this next weekend with the engine in the car. The area between the plug holes and the inner fenders seems a little tight, especially on the passenger side, should I look for a hose extension? Same question on the oil squirter, it doesn't seem as if the oil squirters I've found online have a long enough hose to reach all the holes. I only want to complete this test from the top of the engine, any challenges I should be aware of in advance?
I was thinking of getting this tester:
http://www.sears.com/craftsman-compr...p-00947089000P
Below are the general notes I have, not including the interpretation of the results. I won't have any help so I'm not sure how I can monitor how the compression is building on successive strokes... maybe I can setup my phone to record the gauge? I don't have access to compressed air so no leak down if necessary.
Pull fuel pump relay
Disconect both master ignition relay harnesses
Remove all spark plugs, marking each plug with cyl #
Block throttle body wide open
--begin repeat---
connect compression tester hose to plug hole
Crank for 7 'hits'
Record reading for that cylinder
move to next cylinder
---end repeat---
I was thinking of getting this tester:
http://www.sears.com/craftsman-compr...p-00947089000P
Below are the general notes I have, not including the interpretation of the results. I won't have any help so I'm not sure how I can monitor how the compression is building on successive strokes... maybe I can setup my phone to record the gauge? I don't have access to compressed air so no leak down if necessary.
Pull fuel pump relay
Disconect both master ignition relay harnesses
Remove all spark plugs, marking each plug with cyl #
Block throttle body wide open
--begin repeat---
connect compression tester hose to plug hole
Crank for 7 'hits'
Record reading for that cylinder
move to next cylinder
---end repeat---
I have done compression tests on many engines. it's really not complicated. Now with that said I havent tried one in an fbody so you may have to get creative with the hose depdnign on your kit.
If this is going to be a one time thing just buy a cheap set from HF for 15 bucks or rent one for free at autozone. you dont have to squirt the cylinder with oil or any of that. just pull all the plugs, insert the tester and unplug the fuel pump relay and coils. and crank her over for about 4-6 seconds on each cylinder. thats it. no opening of the tb or whatever else, people make things way too complicated lol
If this is going to be a one time thing just buy a cheap set from HF for 15 bucks or rent one for free at autozone. you dont have to squirt the cylinder with oil or any of that. just pull all the plugs, insert the tester and unplug the fuel pump relay and coils. and crank her over for about 4-6 seconds on each cylinder. thats it. no opening of the tb or whatever else, people make things way too complicated lol
Why are you doing this at all? Are you trying to diagnose something?
As said that kit is a bit much, nice no doubt but a $15 cheap gauge will likely suffice. Over 15 years ago I bought an open package cheap one from Fleet Farm and used it within the last few weeks on my lawnmower, has done boat motors, car and truck engines, snowmobiles etc. over the years. I probably wouldn't buy a $65 kit unless you had some specific need for some extra adapter in the kit. Think my weedwacker is the only engine I can't test with it because of an extra small plug.
As said that kit is a bit much, nice no doubt but a $15 cheap gauge will likely suffice. Over 15 years ago I bought an open package cheap one from Fleet Farm and used it within the last few weeks on my lawnmower, has done boat motors, car and truck engines, snowmobiles etc. over the years. I probably wouldn't buy a $65 kit unless you had some specific need for some extra adapter in the kit. Think my weedwacker is the only engine I can't test with it because of an extra small plug.
Thread Starter
Joined: Jan 2002
Posts: 4,069
Likes: 74
From: Casselberry FL
I drove through a deeper than expected puddle the end of June, and the intermittent backfiring seems to finally have gone away within the past couple of weeks. It still seems like there is some hesitation in the lower RPMs when driving on the highway, so I'd like to get it checked for peace of mind. Changing spark plugs pays two hours, and even if it takes me longer than a shop I'd like to learn something in lieu of paying for it.
I thought about getting one from Harbor Freight but there are reports here that they were crap
I thought about getting one from Harbor Freight but there are reports here that they were crap
