Ok experienced old lags who know classic cars well, try your hand at this.
I went over to help my brother in law with his TR6 issues yesterday and half succeeded. But being a spanner head, I can’t sleep comfortably until we crack it - Hey! I gots to know! (If you’re old enough you know what that means).
The car - 1971 TR6 Pi with the Lucas injection
The symptoms - the car started, warmed up, got to the end of the road and started dying with black smoke coming out of the back.
What we did - checked intake was clear, I changed the points, cap and rotor and gapped them to .45mm (closest I could get to .481 with a metric feeler gauge set and prefer too small to too large). HT leads are new, tested his coil in the Z and it started / revved fine. Sooty plugs cleaned up.
Here are the original points looking very off centre:
We fired her up, warmed up - no black smoke. Went down the road, got twice as far and the engine lost power and was fighting to stall and slowly did. But no black smoke this time so at least one problem solved. She cranks and sparks but would not start again.
I also used my spark plug tester thing and we are getting spark on all 6.
So with electrics eliminated for now, we started to think fuelling.
We can smell fuel coming out of the exhaust when cranking so it’s getting to the engine.
The only thing we can think of is that the injection metering unit may be faulty and possibly putting too much fuel in, hence fouled plugs. It uses a vacuum line from the the inlet on 3&4 to move a diaphragm of sorts. I wonder if that is perished or not getting enough vac so dumping fuel?
Any thoughts or experiences would be appreciated. (He’s also posted on the TR6 forum but I figured there are a lot of very experienced and great mechanics here who may have seen these things with TRs).
Ps. What struck me the most playing under his bonnet is how advanced the Z is compared to the TRs!!! They are properly agricultural. [emoji13]
I went over to help my brother in law with his TR6 issues yesterday and half succeeded. But being a spanner head, I can’t sleep comfortably until we crack it - Hey! I gots to know! (If you’re old enough you know what that means).
The car - 1971 TR6 Pi with the Lucas injection
The symptoms - the car started, warmed up, got to the end of the road and started dying with black smoke coming out of the back.
What we did - checked intake was clear, I changed the points, cap and rotor and gapped them to .45mm (closest I could get to .481 with a metric feeler gauge set and prefer too small to too large). HT leads are new, tested his coil in the Z and it started / revved fine. Sooty plugs cleaned up.
Here are the original points looking very off centre:
We fired her up, warmed up - no black smoke. Went down the road, got twice as far and the engine lost power and was fighting to stall and slowly did. But no black smoke this time so at least one problem solved. She cranks and sparks but would not start again.
I also used my spark plug tester thing and we are getting spark on all 6.
So with electrics eliminated for now, we started to think fuelling.
We can smell fuel coming out of the exhaust when cranking so it’s getting to the engine.
The only thing we can think of is that the injection metering unit may be faulty and possibly putting too much fuel in, hence fouled plugs. It uses a vacuum line from the the inlet on 3&4 to move a diaphragm of sorts. I wonder if that is perished or not getting enough vac so dumping fuel?
Any thoughts or experiences would be appreciated. (He’s also posted on the TR6 forum but I figured there are a lot of very experienced and great mechanics here who may have seen these things with TRs).
Ps. What struck me the most playing under his bonnet is how advanced the Z is compared to the TRs!!! They are properly agricultural. [emoji13]
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