Compression test questions
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Bronze MFP
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Compression test questions
I posted this about a week ago in the KA forum, but didn't really get an answer... I did a compression test last weekend and got ~200 psi across the board, with cyl-3 being just a tad higher (like ~203-205psi)FSM says compression should be ~179psi and no lower than ~150psi or so. Why are my numbers so high? Is it anything I need to worry or do anything about? I know I don't have a KA-T yet, but i'm getting there, thanks in advance to all the engine gurus.
Re: Compression test questions (Bronze MFP)
Well, assuming the engine is stock internally, higher than average compression readings could be from carbon deposits on the pistons. Then again, it could be a bad gauge. Have you tried checking the compression with another gauge?
I suppose you could try running some good old Seafoam (or equivalent...I believe it's mostly Naptha) in the gas tank, but I'd probably leave it alone. You've got even compression across all 4 cylinders, which is great.
I honestly don't know if you'll have detonation problems with a KA-T with compression #'s like that, but I'd really double check them before you do anything drastic.
I suppose you could try running some good old Seafoam (or equivalent...I believe it's mostly Naptha) in the gas tank, but I'd probably leave it alone. You've got even compression across all 4 cylinders, which is great.
I honestly don't know if you'll have detonation problems with a KA-T with compression #'s like that, but I'd really double check them before you do anything drastic.
Re: (S14tat)
Yeah... do a seafoam treatment through the brake booster line. The can has the specific instructions.
Re: (crzycav86)
As I recall, it was a third of the can through the vacuum hose from the brake booster, a third in the fuel and a third in the crank case. I personally changed the oil soon after putting the Seafoam in. Either way, I didn't notice any difference in the performance of the car.crzycav86 wrote:Yeah... do a seafoam treatment through the brake booster line. The can has the specific instructions.
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Bronze MFP
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i'll see if any of my friends has another gauge i can borrow. The one i used, i bought new a few days ago. My engine is completly stock. I figured even though the readings were high, they were very even, so good news on that. I'll try and get some seafoam and see if that works. You get it at NAPA right? Thanks