Need Help with Compression Test Numbers
#1
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Need Help with Compression Test Numbers
So I had a compression check done on the car I am interested in purchasing this weekend. I am not too familiar with these numbers. Going to post them here to make sure they are ok. The inspection says All Areas of the car are in good condition and it say A/C is INOP ( I assume it means In operable but I knew this going in)
Rotor # 1 69.7 82.07 85.08
Rotor # 2 81.05 96.8 90.0
Thanks for any feedback; I am also going to do a search to read up
Rotor # 1 69.7 82.07 85.08
Rotor # 2 81.05 96.8 90.0
Thanks for any feedback; I am also going to do a search to read up
Last edited by wrxsti04; 07-28-04 at 05:26 PM.
#3
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What? yes it starts has a new engine with 3K on the engine Mazda said the #'s where good. Got a compression test done for piece of mind
Last edited by wrxsti04; 07-28-04 at 05:27 PM.
#5
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U guys serious? What are good numbers then?
shop manual says 690 kPa {7.0 kgf/cm2, 100 psi} minimum @ 250 RPM. Differential limit of chambers is 150 kPa {1.5 kgf/cm2, 21 psi} @ 250 RPM.
shop manual says 690 kPa {7.0 kgf/cm2, 100 psi} minimum @ 250 RPM. Differential limit of chambers is 150 kPa {1.5 kgf/cm2, 21 psi} @ 250 RPM.
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#8
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Yeah, that engine is on borrowed time...was it a cold test or after the engine had warmed up? check out this thread for what are good numbers:
https://www.rx7club.com/showthread.p...ht=compression
https://www.rx7club.com/showthread.p...ht=compression
#9
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i agree that that first number on rotor 1 looks like a chipped apex seal, especially being so out of line with the others. even if the numbers are within specs, they should be within 10 percent of each other at the most.
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i just read the for sale thread on this car. looks like a sweet car, but really, those compression numbers are not worth $18k. if he wants knock $2500 off the price, then it might be worth it. i'm basing this on the 93 silver on red in the for sale section that had the same compression numbers you posted.
andy
andy
#14
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yes that is the car. Thanks for double checking. Wonder why the compressions don't seem right. Maybe Mazda Dealer doesn't know what they are doing or did something wrong. I called a rotory specialst and they said the numbers where ok with exception to the 69 was bit concern but not anything big as long as you push normal boast
Last edited by wrxsti04; 07-28-04 at 09:31 PM.
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Well apex seals are a big one, I’ve seen one’s with real badly worn rotor housing end plates have low compression after rebuilds.
But thats all i can real think of right now.
But thats all i can real think of right now.
#19
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Not a rebuild but a Reman new Mazda Engine. The guy has receipts for $4400
I Emailed another rotory specialist here locally for advice and recommendations
thanks
I Emailed another rotory specialist here locally for advice and recommendations
thanks
#21
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Called the Mazda dealership Tech and he said it was good as long as its below 5 or (50)
Probably buying this weekend, pending if all other items I see on the car are in the condition state by seller. Flight already booked, wish me luck
Probably buying this weekend, pending if all other items I see on the car are in the condition state by seller. Flight already booked, wish me luck
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Maybe you should look into getting a second compression test. It's possible that mazda screwed up, but not likely. Remember 100psi is minimum, most would say you could get by with 90 mimimum. Sure the car would probably run another 1-2 years, but you wouldn't be able to drive it like you want to. Like others mentioned you should see if you could get the guy to knock off a couple grand.
#23
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Originally Posted by wrxsti04
Called the Mazda dealership Tech and he said it was good as long as its below 5 or (50)
Probably buying this weekend, pending if all other items I see on the car are in the condition state by seller. Flight already booked, wish me luck
Probably buying this weekend, pending if all other items I see on the car are in the condition state by seller. Flight already booked, wish me luck
[edit] btw after reading this whole thread. Move on, dont go with this one.
Last edited by Fatman0203; 07-29-04 at 11:05 AM.
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Originally Posted by Fatman0203
How much cash does the guy want for it?
[edit] btw after reading this whole thread. Move on, dont go with this one.
[edit] btw after reading this whole thread. Move on, dont go with this one.
#25
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Originally Posted by wrxsti04
I am starting to think the numbers I posted are confusing people but maybe they did mess up. Mazda said the engines fine so I might run with this one. Obviously going to test drive it first