Inline Guys, I've finally begun tearing into my GMC 270 to ***ess its general condition and what will be required to bring it back to life. The motor turned over great, but once I removed the head, the horror show began with a chunk missing out to the top ring land of a piston and signs of a blown head gasket. it looks as though the material blew through the exhaust andfragments didn't make it past the rings into the crank case. All the pistons slid out of the bores without necessitating the use of a ridge reamer (however a few pistons had broken rings so that could have been the result). I removed the main caps and rod caps and the bearings are severely worn with copper showing through the bearing material. There was not much in the way of gouging and scoring of the bearing surfaces and journals. The journals might need turning but look decent. The cam and lifters look to be in good shape also. Sorry for the long winded preamble, here's where I am getting stuck: I am unable to remove the timing gear and also the timing plate behind it. I fabricated a puller of sorts using a piece of 3/8" steel with holes drilled at the same spacing of the threaded holes of the timing gear. I am using two long bolts through the holes in the plate going into the timing gear, with the plate resting at the edge of the crank snout to create a puller of sorts. I stopped as it seems the gear doesn't want to budge and I don't want to strip any threads etc. I removed all the bolts from the plate including the ones on the inside of the case and the countersunk flathead screws. The plate still seems to be attached to the block somehow as it will swivel on an axis around the timing gear at the 4:00 position. Wondering if anyone had some sage advice? I want to mic the crank etc.
Here’s some pics. Please save me from considering the spare SBC sitting in the corner of the garage! I have a feeling this motor may become a money pit.
The gear is an interference fit. It's installed by heating it and ,or cooling the cam. Remove the plate retaining bolts and remove the cam and gear as a unit.
We used to set those timing gears on a hot plate that I have or back when I had my 59 El Camino with the 235 on the burner of the kitchen stove and get it hot to expand it and run out and stick it on the cam. In the 70's I had gotten a new job as a mechanic at a Firestone store and on my way to my old job to tell them I was leaving the timing gear went out on my Elkie and I caught a ride to work and told my boss I had found a job at the Firestone store and we loaded my tools in his truck and he hauled me up to the tire store and set me out and I worked there for several years with much larger pay checks. Then his son came by and picked me up after work and helped me tow my truck home as he lived a few blocks from me.
I was able to get the cam out no problem, it's the steel plate against the block that the timing cover bolts to that seems to be stuck to the block. I can't see any fasteners that I missed. thanks.
Yes. I removed the 2 bolts and the main cap. It’s really weird. It’s swiveling near the 4:00 position near the timing gear on the crank. I can’t see what’s holding it in and don’t want to force it or bend the plate like the gorill that I am. Thanks
Whelp, I’m a bona fide idiot or my eyes are failing me. I can now see the screw I missed in my own photo! Thanks for the replies.
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