Super Jet cylinder compression issue
- Thread starter Ahmed AN9
- Start date
I rebuilt the top end last year and it was fine.
- Location
- Nor Cali
Maybe try your stock head then test the compression. If it's still low, it's time to check your rings.
bored&stroked
Urban redneck
- Location
- AZ
And now its not. Only so many options here.
OK when i attempted to tighten the head bolts I found two bolts are unable to be tighten loosing the threads on the holes. So I decided to remove the cylinder to send it to machine shop for rethreading then what I found is in the pictures below and the exhaust gasket melted and stuck on the cylinder and the muffler wall. Any idea given by these findings???? 
Blue
Judging your cheapness
- Location
- St Cloud Florida
Have the top of the cylinder milled or surfaced. I bet its warped or the sleeves have dropped a little.
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Sent from my SAMSUNG-SM-N920A using Tapatalk
What do you mean by the sleeves dropped? how can that happend?
I tried but still the same. Am concerning the head bolts torque and the two damaged threades.
Judging by the photos, you have 701 cases with a 701 62T cylinder that has been bored to 85mm.
I agree. Definately 62t/701 cases becuase of the single pulse. Cylinder looks like 62t 701 as well but a little hard to tell from the pics.
Piston wash is off on front cylinder as compared to the rear.
Zero Client
BeerrroooOOOT!!!
- Location
- Douglasville, GA
My bet is this is a 701 waveraider engine which is 62t-y1. This is not a 61x setup. Dual 38mm carbs likely.
Zero Client
BeerrroooOOOT!!!
- Location
- Douglasville, GA
Stripped bolts in the cyl/head are easy to do. Use a torque wrench next time. You can use helicoils to fix. A full girdled head will also help hold the head and cyl down.
- Location
- Granbury, TX
Where is your cylinder base gasket? Pictures look like none was used... Something isn't right for your compression to be that low. Can you feel the scratches in your cylinders with a fingernail?
Also, when you're checking compression do you have the throttle pulled wide open?
Also, when you're checking compression do you have the throttle pulled wide open?
The base gasket is there but I took it out with the cylinder.
The scratches are not deep and can't be felt by fingernails.
I tried three different ways in compression test one of them while the throttle is wide open.
Zero Client
BeerrroooOOOT!!!
- Location
- Douglasville, GA
Not sure. When you get it back together you can check for basic leaks by way of low pressure tests.
62t 701, you can see the sleeves.
My advice to the owner but who really cares; ditch that over bored worn out cylinder and pistons.
Do you mean that I have to take out the sleeves and put new ones??