Today's project: PKensioner and timing belt install
#16
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#18
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Well, I got the PKensioner installed and the timing belt on...followed Ken's instructions to the letter...after removing the grenade pin on the tensioner, and rotating the pulley CCW lightly to pretension the belt, I found the piston extension to be 9mm. This is a new Gates racing belt.
Another complication...this car had its heads replaced about 10 years ago, but less than 10K miles ago. They were used heads, and there is no indication of the heads being machined at that time...but they were used heads. I am thinking there is a good chance they were machined, which might explain why I am at the upper end of the extension range.
Since I am using the Gates belt, and it is new, do I really have to worry about reaching the 11mm max extension on the piston? Ken recommends drilling out the tensioner bolt holes if extension exceeds 9mm.
Another complication...this car had its heads replaced about 10 years ago, but less than 10K miles ago. They were used heads, and there is no indication of the heads being machined at that time...but they were used heads. I am thinking there is a good chance they were machined, which might explain why I am at the upper end of the extension range.
Since I am using the Gates belt, and it is new, do I really have to worry about reaching the 11mm max extension on the piston? Ken recommends drilling out the tensioner bolt holes if extension exceeds 9mm.
The Racing belt doesn't stretch, so you could leave it alone.
The 7mm max start spec assumes a 2mm stretch from new with a standard belt to 9mm.
Add 2mm for a wintertime cold engine to 11mm.
I would probably say: drill out the holes anytime the heads have been milled.
#19
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Thanks, I really appreciate the reply. I am leaning towards leaving it alone, but I will think about it over the holiday.
The shop that did the heads wrote almost the whole thing up as labor (because in Maryland we only have sales tax on parts). There is only a set of plugs, some oil and coolant, and a few other small parts itemized on the invoice. I would normally itemize machine work as a sublet on the ticket, but they were clearly trying to keep the job under $3K for the owner at that time (they also did a timing belt and water pump, with metal impeller...this was in 2004).
The shop that did the heads wrote almost the whole thing up as labor (because in Maryland we only have sales tax on parts). There is only a set of plugs, some oil and coolant, and a few other small parts itemized on the invoice. I would normally itemize machine work as a sublet on the ticket, but they were clearly trying to keep the job under $3K for the owner at that time (they also did a timing belt and water pump, with metal impeller...this was in 2004).