compression and leakdown results
So the truck ('58 292, Mallory dizzy) has been running like a dream thanks to everybody here but lately I have noticed a lot more fumes coming out the down draft tube so I decided to do a compression and leak down test to see what was going on, kind of wish I hadn't. The compression was right around 100-110 across the board but I was thinking that my gauge might not be working right because it would jump up to that number and right back down to 0, I never had to release the pressure. Then I did the leakdown test with 80 psi it would drop to around 20 on the cylinder side and my little compressor had a hard time keeping up with the amount of air that was rushing by. Had it at tdc, with the choke closed and accelerator plate wide open, no air cleaner on. It sounds like the air is going passed the rings and or the valves (I know "really narrowing it down") because I can hear it coming out the dipstick I think. My question is, with the numbers could I really have the truck running so nice, it sounds like clockwork? Thanks to all in advance.
Regards,
Cbass (Sebastian)
The bad news you already know, and will be a little more spendy to deal with.
With all the blow by it's hopefully just worn rings and you could hone the cylinders and replace the rings if you are on a tight budget, do you still have good oil pressure.
Although you know a complete rebuild would get you down the road for many years.
Good luck in your quest.
Oh, and this is just me but I never bother with leak down tests. The compression test and a vacuum gauge will tell me everything my lazy butt needs to know about engine condition.








