The ones that u screw it in just like a spark plug than u read it … ummm … anybody know where i can rent one ? or owns one that i can borrow for a day ?!
I got 2, but I live 500KM’s away.
Crappy tire now rents alot of tools. Doesn’t cost anyhting either!! they take a deposit and you just borrow them. Bring it back in nice shape…get all your money back!!
I don’t know if they rent compression testers however.
Another option. Go to a shop, pull the plugs yourself in the parking lot, and then it will only cost you like $20 or something for them to come check it real quick!!
Run to Princess auto, I bought mine for like $25.
I have one for 30 at partsource if you want
closer than princess auto but a little more money
That’s just off the top of my head, it might have been even cheaper since I did get it on sale.
Part Source has them for 30 dollars ?!
and is turning the motor over once is good enough ? or do i need the dumb tools to actually crank it manualy ?
No, crank it till it stops going up.
Usually 3 compression strokes is enough.
Yes the do
Best way to do the test is with 2 guys. loosen all plugs, blow around plugs to remove dirt ect… so it doesn’t just fall in combustion chamber. remove plugs. attach screw in end of comp.tester. Hold bleed valve open and get buddy to turn engine over once.(blow it out) then release bleed valve, have buddy crank it over and each compression stroke the needle will rise up a little. Keep cranking untill needle stops going higher. Stop cranking(ussually 3-5 full turns). Hit bleed valve to release pressure. Unscrew and repeat!
Pull all your plugs before testing. Disconect your spark, unplug coil(s). turn off fuel(fuel pump fuse) This is called a dry compression test. Don’t crank engine over forever as there is no oil flowing while you do this, but alittle while is OK. If you don’t turn off fuel(not everyone does) the gas will wash the oil off your cylinder walls, lowering your compression and increasing chance of scratching inside.
Hope all that helps!
Why won’t there be oil flowing?? Your crank turns the pump?? Maybe you are confused.
And your injectors aren’t going to inject enough fuel in 20-30 revolutions to cause damage.
Just telling you what I was told when I was an apprentice mechanic. If you know something I don’t that’s cool, just passing on the knowledge I have and the way I do things!
Your oil pump doesn’t really create any pressure at that low of RPM. once your engine has started it still takes a second untill pressure is up.
And it only takes one little squirt of fuel to wash off you cylinder walls. They aren’t covers in oil, they have a tiny tiny film coating, doesn’t take much for it to wash off.
But again…this is my opinion or what has been taught to me. Please share your opinions or knowledge as well.
Thank you very much for the extended info…
In order to save some bandwidth, i am going to ask another quick question in this thread…
My oil pressure is constantly running high, always above average and closer to the top, doesnt matter if i drive nice or slow … what could be a reason ?
Well if you’re just doing a compression test unplugging the fuel pump won’t do anything as there is already enough fuel supply at the injectors to cause them to inject fuel for a while regardless of the pump being on. It’s not a bad idea as a safety precaution, but an easier way to ensure lubrication would just be to spray a little wd40 into the cylinder you are testing. The engine should be warm when you are doing the test, so there should already be plenty of oil sitting in the head.
Slide: Is this just your factory gauge showing this pressure? Does it ever change levels as the vehicles warms up or the RPMs change? If not you might have a faulty sending unit or gauge. If not, a restriction in the system could be causing excess pressure - plugged filter, plugged oil galley somewhere in the engine. Not a good situation regardless.
Yes it is my factory oil gauge … when its idling it sits at normal but soonest i start driving(well at least when i used to), its up there almost maxed doesnt matter if i drive nice and slow or fast… rebuillddd timeee
might be the guage, those factory ones are ussually not accurate after 15 months, not to mention 15 years!!
This has the original engine or a swap? that might effect it too.
Could also try a engine “flush” product next time you do an oil change. That can help get deposits and build up out of the galley’s.
About the compression. I have never heard of trying WD40, but It is common to squirt allitle oil in right before testing. That’s called a wet compression test. And you could be right about not needing to unplug the fuel pump other than as a safety measure, Safety measures are a common thing to be taught. With the fuel pump off, wouldn’t the fuel pressure drop?
I do have one of those Engine Flush pint thingies actually … Didnt know if it was a good idea or not… but will sure do…
and 15 years ? try 22
Yes the pressure would drop, but for the amount of fuel injected at idle the rail has more than enough to supply four injectors for 20 revolutions of the engine.