When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I'll try and be brief and to the point as possible. 1995 Ford F250, 5.8w motor. I acquired a bad miss and found I had 0 compression on the left front cylinder. After I pulled the head I found a chipped valve and replaced it. I pulled the other head off to replace the gasket while I was in there. I put the heads back on, torqued the rockers to 18 foot pounds, immediately after did a compression test to see if I had any compression problems with my job. Only to find that a few of the cylinders had 100-115 pounds compression while others had 150. I loosened off the rockers and found that those weak cylinders jumped to 150 psi. SO obviously the valves are set too tight, however, I don't know why. My only theory is, that the lifters are not giving at all. I started to check them by disassembling them and found that they were sticking/seized. Could that be my problem with the valves being set too tight, or are they supposed to be almost impossible to collapse when they are charged? I put a hell of a lot of force on a couple to try and get them to collapse while charged and they didn't budge. HELP?
Rockers should be torqued to 25 ft/lbs. If the lifter plungers are fully compressed with the rockers torqued, then your pushrods are too long. Are the rocker fulcrum channels in place under the pedestals ? Have the heads been milled ? What head gaskets did you use ? Now if the lifter plungers are sticking or seized, they should be replaced, if there's that much gunk inside them I'd hate to think as to what the bearings in the bottomend look like.
Rezvani's Latest Post-Apocalytic Monster Is a Ford F-150 Raptor Underneath
Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.