How can I check the compression on an engine without the transmission
#1
How can I check the compression on an engine without the transmission
checking compression on an engine without its transmission?
well I've never worked on a rotary but I've always bolted on the starter and it turns the flywheel and vuala compression happens so can someone tell me
why it cant be done on the 13b-rew I have an engine I wanted to go see for my shell .. but the owner is selling it for quite a bit because he says it has 120 compression but he never tried it.. because it has no tranny or harness
which brings me to another question . is it difficult to buy a harness and plug it all in ? and well I can find a tranny ..
well I've never worked on a rotary but I've always bolted on the starter and it turns the flywheel and vuala compression happens so can someone tell me
why it cant be done on the 13b-rew I have an engine I wanted to go see for my shell .. but the owner is selling it for quite a bit because he says it has 120 compression but he never tried it.. because it has no tranny or harness
which brings me to another question . is it difficult to buy a harness and plug it all in ? and well I can find a tranny ..
#3
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I'll wait for the gurus opinion, but thinking that to check dynamic compression you'll need a transmission and starter. If the engine is out, maybe you could use a big impact at the flywheel nut or front hub.
If in the car, you could turn it by hand but I don't think that would tell you much. I think turning it that slowly compression would leak down some past the seals no matter how tight the engine.
If in the car, you could turn it by hand but I don't think that would tell you much. I think turning it that slowly compression would leak down some past the seals no matter how tight the engine.
#4
I'll wait for the gurus opinion, but thinking that to check dynamic compression you'll need a transmission and starter. If the engine is out, maybe you could use a big impact at the flywheel nut or front hub.
If in the car, you could turn it by hand but I don't think that would tell you much. I think turning it that slowly compression would leak down some past the seals no matter how tight the engine.
If in the car, you could turn it by hand but I don't think that would tell you much. I think turning it that slowly compression would leak down some past the seals no matter how tight the engine.
#7
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I'll wait for the gurus opinion, but thinking that to check dynamic compression you'll need a transmission and starter. If the engine is out, maybe you could use a big impact at the flywheel nut or front hub.
If in the car, you could turn it by hand but I don't think that would tell you much. I think turning it that slowly compression would leak down some past the seals no matter how tight the engine.
If in the car, you could turn it by hand but I don't think that would tell you much. I think turning it that slowly compression would leak down some past the seals no matter how tight the engine.
John
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#9
Wastegate John
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^ Depending on what size impact you use. I used a 3/4" impact gun to tighten my flywheel nut. I did not need to use ant type of tool to "lock" the engine from spinning. I know it is supposed to be torqued, I choose not to care. I know it is tight enough.
If you keep trying to turn the engine using the impact gun, the impact gun will keep hammering, it does not apply the force long enough to turn the engine (hence the hammering). Think about this, you jack the front wheel up in the air of your FD. You forget to loosen the lugs before you did that. If you use an impact gun (assuming you have crappy or stock lug nuts) the wheel does not turn. You do not have to hold the brake to use an impact gun even if the wheel is up in the air able to free spin. And I am sure we can agree, the front wheel is a lot easier to spin than an engine making any compression.
Hope that crappy explanation makes sense.
John
If you keep trying to turn the engine using the impact gun, the impact gun will keep hammering, it does not apply the force long enough to turn the engine (hence the hammering). Think about this, you jack the front wheel up in the air of your FD. You forget to loosen the lugs before you did that. If you use an impact gun (assuming you have crappy or stock lug nuts) the wheel does not turn. You do not have to hold the brake to use an impact gun even if the wheel is up in the air able to free spin. And I am sure we can agree, the front wheel is a lot easier to spin than an engine making any compression.
Hope that crappy explanation makes sense.
John
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Wastegate John
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^ No problem with thinking out loud.
Edit: Maybe OP can find a bad transmission... Like one with a hole in the case. And just cut off the bellhousing, then just bolt that up to the engine to check compression. If the transmission is not local it could be shipped a lot easier than an entire transmission.
John
Edit: Maybe OP can find a bad transmission... Like one with a hole in the case. And just cut off the bellhousing, then just bolt that up to the engine to check compression. If the transmission is not local it could be shipped a lot easier than an entire transmission.
John
#14
I have no transmission at all as the car was purchased as a shell .. w/o out I can buy one on its own but then that limits my engine choices since alot of long blocks come with transmissions , he was asking for 1700 for an unrebuilt , stock jdm engine . with unknown miles . no harness , or ECU , or trans
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I'm not sure how that's an option. $1700 for an unknown miles, unknown condition engine is absurd, even with a transmission thrown in. You can get a clean rebuilt short block for not much more than that from a number of reputable vendors.
I still will never understand why anyone would want to put an unknown condition engine in a car. That's a lot of effort to put the engine in and have it go *puff* *squeak* *squeak*
I still will never understand why anyone would want to put an unknown condition engine in a car. That's a lot of effort to put the engine in and have it go *puff* *squeak* *squeak*
#18
I'm not sure how that's an option. $1700 for an unknown miles, unknown condition engine is absurd, even with a transmission thrown in. You can get a clean rebuilt short block for not much more than that from a number of reputable vendors.
I still will never understand why anyone would want to put an unknown condition engine in a car. That's a lot of effort to put the engine in and have it go *puff* *squeak* *squeak*
I still will never understand why anyone would want to put an unknown condition engine in a car. That's a lot of effort to put the engine in and have it go *puff* *squeak* *squeak*
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