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Discussion Starter #1
My car feels like it runs great, pulls strong, just a slight stumble at low rpm. I checked the spark plugs today just to make sure they weren't fouled. #3 plug was completely blackened. I wasn't sure if it was oil or gas on the diode so I put a new plug in and drove around the block. Pulled the plug after my short trip and again, the new plug was already looking dark. I tried wiping the plug clean but it wouldn't come off (wouldn't oil come off? I'm assuming this is from a rich condition?)

Anyhow I decided to run a compression check and the #'s in the title were my results. Again, the car feels strong, doesn't overheat, and doesn't stall, so I'm curious as to what my next step should be. If I were to throw oil down the cylinders to check the rings, how much? Just a cap full?

Is there a way to re-seat the valves, that a shade tree mechanic can take care of? Say I do need new rings, is it possible for us Lotus guys to change out rings with the motor still in the car? Any guidance would be much apreciatted.

Any Recomended Lotus gurus around Texas that I could trust for a rebuild?
 

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Hi--I don't have many posts on this forum so I am going to humbly ask that you tell us which lotus you have.

Thanks.
 

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Next step would be to do a leakdown test, and positively identify whether the compression problem is a valve or piston ring issue.
 

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Discussion Starter #9
hey guys, car is an 06 exige

I think a leak down will be my next step. One question, could it possibly be a head gasket issue? One side of the head having such low compression is kind of suspect to me.

Oil consumption is normal. I dont notice in increase in oil loss or anything. Let me ask, when my number 3 cylinder went, the spark plug was extremely fouled. Had a lot of black gunk on it, basically a ton of build up. Im not sure if it was oil or what but it was fouled to the point of not working and completely black. Does this sound like blow by past the rings?

Also, if its a valve issue, normally what causes this? Poor timing? kinked valve? worn valve seats? Just curious and still learning. Thanks alot for your continued support.
 

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Since two adjacent cylinders have the same low compression, my suspicion is that it is a head gasket leak between the two cylinders. Although IIRC, blown head gaskets sometimes leave evidence of coolant from the head leaking into the oil.

Check the coolant level. How has the water temp been? If the engine overheated, then some heads are prone to warp (don't know about 2ZZ specifically). If it's just a blown head gasket, that's not a huge job -- any Toyota mechanic should be able to do it.
 

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Discussion Starter #11
Since two adjacent cylinders have the same low compression, my suspicion is that it is a head gasket leak between the two cylinders. Although IIRC, blown head gaskets sometimes leave evidence of coolant from the head leaking into the oil.

Check the coolant level. How has the water temp been? If the engine overheated, then some heads are prone to warp (don't know about 2ZZ specifically). If it's just a blown head gasket, that's not a huge job -- any Toyota mechanic should be able to do it.

I have not noticed any coolant loss, but I should probably check. Also havent cheked oil consumption so ill see if its on the low side. My temp has been rock steady at 190 degrees, never goes over. Like I say, the car drives fine, never stalls out, and doesnt overheat. Only thing abnormal is a slight sputter at very low rpm's and the #3 spark plug fouling out after a while.

Let me ask, will a leak down test give you tell tell signs of a leaking head gasket? Thanks so much for the reply Kermit.
 

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Discussion Starter #15
Ok guys, just purchased a BOE nicasil bottom end and paired it up with a Jim Clayton Ferrea head. I will let you know how everything goes from here on out. I saved about 10k going this route over the k-series I originally had planned, plus I get to keep AC [ROCKON]
 

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Discussion Starter #17
Sorry about the results of the tear down. Glad to hear you are on the road to repair.
Thankyou sir. Im excited because Im getting the weak spots in the motor taken care of. Now I dont have to worry about high rev's or tight turns. Love the color of your car btw.
 

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Ok guys, just purchased a BOE nicasil bottom end and paired it up with a Jim Clayton Ferrea head. I will let you know how everything goes from here on out. I saved about 10k going this route over the k-series I originally had planned, plus I get to keep AC [ROCKON]
Happy to hear you're on your way to getting it running again. What was the original problem?
 

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Discussion Starter #19
Happy to hear you're on your way to getting it running again. What was the original problem?
Not sure as of yet. Ive been away on work for the last 2 weeks and havent got to tear her down yet. When I receive my parts, better believe Ill be taken a PLETHERA (Did you just say...plethera?) of pics.
 
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