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Valve timing

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Picked up the re-cored radiator today. Looks like a new one. Cost was $337.88. Better than the $800 new plus shipping! Will recheck the timing gear position one last time tomorrow and then button it up. Had to cut wood today.

I feel like I can play with the big kids now because I know what the Dizzy is! Sarge
 
Ed, I must say that I have been slacking off on the Healey. Still getting some wood in for the winter. I ended up ordering a new timing chain because I was afraid the old one was stretched (worn). There is no significant diference between the new and the old one however. The weather is good and the leaves are turning so I better get it together so the wife and I can enjoy a ride in the autumn air.
 
Finally got a chance to get after the long delayed timing chain project this afternoon. After resetting the distributor timing and valve clearence I checked the compression again and found it still to be 85-95 psi in all the cylinders. When I started the engine, it still had its famous backfire through the intake until it got hot then it diappeared. As soon as I have a chance, I'm going to remove the carbs and go through them and adjust them. I believe the engine needs a rebuild at this point but will put it off. I am not sad that I went through this exercise because I now have a new oil seal infront and I learned a lot. Don't like a day when I don't learn something. Thanks to you all for your guidence. SargeVT
 
Well Sarge it seems you beat your schedule since you got it runing on Sunday instead of Monday. Sorry to hear that the backfire was not corrcted but with compression levels that low I also think it will take a rebuild in the near future.While you were cuttin wood did you make up some kindling too.??---Keoke /ubbthreads/images/graemlins/grin.gif
 
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When I started the engine, it still had its famous backfire through the intake until it got hot then it diappeared.

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Hi Sarge,
This would indicate a lean mixture. Likely suspects are carb problems or intake air leaks. The lean mixture burns so slowly that it is still burning a bit when the intake valve opens.
D
 
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When I first got my BJ8, it would backfire through mostly the rear carb every time I gave it some gas. After checking the valves and carbs, I replaced the old coil and points with the Petronics ignition pickup and matching coil. The backfires were 100 % gone after that.

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Hi Sarge, You might try this trick of "ED'S",it may help, also opening the valve lash to about 0.015" may aid a bit too.---Keoke
 
When I had the backfire problem, I pulled the plugs and saw that they all were wet. I cleaned them up on the wire wheel and checked the gaps. It already had a new rotor and cap. Also the point gap was OK. I tried it again and still had the backfires. I then remebered an old experience trouble shooting a rough running sprite that a highschool friend owned. That lucas coil was only 10 years old and caused the
hard to diagnose problem. My lucas coil was 40 years old, it may be time to just replace it. I got lucky and then also installed some new bosch platinum plugs gapped at .035 along with the petronics hall effect ignition pickup. Never had another hint of a backfire since then. I guess I have rambled on enough, check for wet spark plugs... I almost forgot, ( C.R.S. ), the old coil checked across the primary indicated 12 to 14 ohms, not the 3 ohms that it should if it was good. That is probably the best way for one of us to see if the existing coil is any good.
 
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When I started the engine, it still had its famous backfire through the intake until it got hot then it diappeared. SargeVT

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Folks,
Remember Sarge said the problem goes away when the engine is warmed up. Ignition problems usually DO NOT go away when the engine gets warm.
D
 
Dave, I agree that if the problem truley goes away as it gets hotter, it is less likey to be ignition. Mine would " improve " as it got hotter, but never went completely away. Also, it is very easy to put an ohm meter on the coil and pull out a couple of plugs to see if they are damp. And last but certainly not least, I suspect that anyone that still has an original lucas coil on their car from the 50's-60's would do well to suspect/check it 1st at the 1st sign of backfires and/or rough running that can't be fixed with points and timing adjustment.
 
Ed, Just before I installed the new timing chain, I put a new coil on because after driving about 10 miles, it would start to skip. The new coil took care of the skip but it didn't take care of the back-fire. I believe I am starting to narrow the problem down so will go after the carbs as Dave suggests. I have checked for leaks with both WD40 and quick start but that didn't seem to indicate any air leak problems. I rebuilt the carbs several years ago trying to solve the problem without any success. I believe I know a lot more now about them so will give them another try.

Keoke, Does the valve lash increse with temp? I know that they are set at .012 now. If it does, maybe that is why it is better after the engine is hot. Sarge
 
Have you by chance taken a dial test indicator and measured your valve lift? If your exhaust lobe on the cam is worn, when the intake opens the exhaust will escape out the intake causing a popping / spitting sound similar to the sound on your video clip. GM had a problem with soft cam shaft lobes in the late ‘60’s and the first indication was a popping / spitting sound at the carburetor.
 
HI Sarge, No not to my knowledge valve lash does not change significantly if the engine is runing witin its specified temperature range.---Keoke
 
I received my rocker arm assembly back from Rocker Arm Specialists. They did a great job, $144. Anyway, I was reading this post to reaquaint myself with the rule of 13, to adjust the valves. Since I don't have a socket that will turn the crankshaft and there appears very little room to get a wrench in there anyway, I thought about pushing to car forward in third gear to turn the engine, as suggested. Then a friend mentioned to just jack up the right rear wheel and hand turn it in third gear. It sure is easier than pushing the whole car and a lot easier to get the right valve fully open to adjust the appropriate gap in the cooresponding (13-X)valve. Just thought I would pass that on.
 
Just put it in neutral Shorn, and use the button on back of the solenoid to turn the engine.---Fwiw---Keoke
 
That certainly works too, but it seems easier to keep things in order just moving the RR wheel, a little more control than bumping the engine along with the starter.
 
To me it seems more difficult, Shorn, going back to the rear wheel, turn it a bit without seeing the opening and closing valves overlap...
For me the "push the whole car in 3rd or 4th" worked very well...
 
almost sounds like a "cold joint" problem, as in when a soldered joint is loose when cold but when warmed up closes the gap and works ok
tried the sol method myself, but it either overruns or kicks back from desired stopping point!
 
ZBLU, Use the engine fan to precisely position the engine after bumping with the solenoid.---Keoke /ubbthreads/images/graemlins/yesnod.gif
 
Keoke, that is how I set the valves in my BJ8. Seemed to be the easiest for me. Have used the wheel method in other cars however. Since I don't have a warm garage, I haven't got to the carburators yet. Sarge
 
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