So yesterday I overheated due to hose not being properly secured. So today after having my blazer towed home I did a compression test results are not looking good got about 180+/- on 1-2-5-6 but on 3 and 4 I got around 120. My question is would this be head gasket or not seems I thought that was when it's adjacent cylinders not when they are across from one another. Also how would I go about putting oil in those cylinders to figure out if it's rings or maybe valves seems the plug holes go in at an years angle. All help appreciated.

 

Not a headgasket most likely valve train issue. Was also just thinking if you got the compression test tight all the way on those two cylinders that could also be the issue probably should redo the test.

 

first, why did you do a compression test? I understand about it being overheated and all, but I had a 98 blazer that overheated 3 times before it blew the head gaskets. honestly, I don't think its the head gaskets, I think it would be the valves, or piston rings.

also to put oil in the cylinders you can get one of them small syringe like what you use to give baby's medicine with. that would work, I've used it a lot on engines.