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View Full Version : Wedge TR7 Head Job



Dale
02-19-2008, 12:19 AM
Just a quickie to say hello again and report on a good result to changing the head gasket and water pump on my 1981 TR7. Had, since the rebuild of the engine 30,000 miles ago, been getting combustion pressure in the header tank, with resultant loss of coolant. Lived with it for 5 years and 30,000 miles until it started putting coolant into the crankcase at a fast pace. Head came off easily, gasket blown at rear of cylinder 4 into water jacket and apparently had been that way for some time. Head torqueing ritual had not been followed after rebuild. (my bad) Replaced head gasket, O-ring, and water pump. Performed head torqueing ritual, and will torque again at 500 and 1000 miles. Result is, no combustion pressure in system, no coolant loss, and no overheating tendancies. Must now check thermostat for sticking, as it takes forever for it to warm up. Cannot see any reason for the water pump to be leaking, but read a warning somewhere about soft shafts that wore rapidly and leaked. As usual was sorry I had put off the job for so long as it was only the usual bother and not the unusual bother. If I was to do it again I would use the reccommended alignment studs for mounting the head and pay closer attention to the distributor clip that got under the head on the first attempt. All in all a good result and we are looking forward to traveling in the 7 to Tucson on the 28th of this month.

tr8todd
02-19-2008, 09:54 AM
Way back when I had a TR7 for a daily driver, I would retorque the head bolts at every oil change. They have a tendency to slacken some how. By backing them off slightly and then retightening them, I think it will help in removing them if it ever becomes necessary again.

TR3driver
02-19-2008, 07:07 PM
Cool, thanks for the report. Gives me hope for the Stag engine with the leaking head gasket (even tho I already know the studs are seized in the heads).

Dale
02-19-2008, 09:39 PM
Yes, I was fortunate that when the head was installed 30,000 miles back that an anti sieze compound was used on all the studs and bolts. The studs came out readily.
From my experience with a junker, I know the head can be removed with the studs still in the block, but the front timing cover must be removed along with the cam chain and sprocket.
When my engine was rebuilt the head had to be destroyed to remove it. The head on the junker I had was unusable as it had been improperly machined during a previous rebuild such that the cam bearings were in a bind and showed horrible and strange wear patterns. That engine did contribute it's .020 OS pistons to my engine and a number of other bits as well.
What I've read about getting a stuck head off seems to emphasize patience and much penetrating oil and lots of time for it to work and soak in. Patience is not a virtue I posess much of so I am doubly glad for the recent rebuild and the anti sieze. Y'all take care and good luck.