Hi Guest!
Hey - did you know if you click on the title of a thread it will take you to the first unread post since you last visited that thread?
but were afraid to ask: 
STOP!! Never post your email address in open forums. Bots can "harvest" your email! If you must share your email use a Private Message or use the 
smilie in place of the real @
Pretty Please - add it to our Events forum(s) and add to the calendar! >> 
When we last left our hero, he was still battling the dreaded TR7 backfire problem. With his forum friends' help, he tracked down a number of problems, but still the backfire remained.
-We checked the carb bypass valves, which both looked perfect, and we set them, which solved the slow throttle drop-off...but the pop remained.
-We checked the carb piston movement, and with only 2000 miles on the car since new carbs, they were perfect, and the back-fire was still present.
-We checked the exhaust manifold, and found a bolt missing. We replaced stripped and missing bolts, torqued them all down, but still the pop remained.
- We checked all the hoses, and all seemed tight.
FINALLY...
- We checked the smog pump check valve -- pulled it off and breathed through it. It seemed tight. Put it back on, and after a minute of no backfire, the backfire returned.
...so today I clamped the rubber hose leading to the check valve, and (drum roll please...) the backfire disappeared.
Now all I have to do is find a source for a new air pump check valve! /ubbthreads/images/graemlins/cool.gif
-We checked the carb bypass valves, which both looked perfect, and we set them, which solved the slow throttle drop-off...but the pop remained.
-We checked the carb piston movement, and with only 2000 miles on the car since new carbs, they were perfect, and the back-fire was still present.
-We checked the exhaust manifold, and found a bolt missing. We replaced stripped and missing bolts, torqued them all down, but still the pop remained.
- We checked all the hoses, and all seemed tight.
FINALLY...
- We checked the smog pump check valve -- pulled it off and breathed through it. It seemed tight. Put it back on, and after a minute of no backfire, the backfire returned.
...so today I clamped the rubber hose leading to the check valve, and (drum roll please...) the backfire disappeared.
Now all I have to do is find a source for a new air pump check valve! /ubbthreads/images/graemlins/cool.gif
