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distributor 180 degrees out

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bluemiata90

bluemiata90

Jedi Trainee
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I just started to do the mechanical on my 1961 TR3 and have run into some very interesting previous owners surprises. The dist. that was installed was not working correctly,Missed and died. I switched out dist. with another one from same year TR3 and it appears that the timing gears my have been installed 180 Degrees out. The engine had been rebuilt. The dist. wouldn't install with the #1 piston at TDC with the timing marks lined up. When I installed it 180 degrees out, it started right up and seems to run good. Is this possible that it is 180 degrees out., I installed a pertronix ign. so I'm not sure how to check the static timing to see if it is correct. Any thoughts or help would be greatly appreciated. The way it is now, I can't find a true timing mark to time it with my light. Help.
 
First verify that you do have number one cyl @ TDC, you can do this roughly by removing the valve cover and peering thru the sparkplug hole as the piston comes up and then verifying that both rockers are free to move. Then take a look and see were the timing mark is. The front pulley is consists of two halves and since it has six holes it is very easy for someone to install it incorrectly to the front crank piece and thus your timing marks will be off. If the timing mark does line up then the DPO or his evil helper installed the distributor drive gear incorrectly. /bcforum/images/%%GRAEMLIN_URL%%/mad.gif
The Bentley manual has instructions as to the correct alignment of the drive gear. /bcforum/images/%%GRAEMLIN_URL%%/hammer.gif
 
When the timing marks show TDC, both #1 and #4 pistons are at TDC, but only one of them will have the valves closed ready to fire. If you turn the crank 180 deg., the vavles on the other cylinder will close. You'd have to take the valve cover off to see which set of valves are closed. Also, I believe the dog on the distributor can be installed 180 deg out. When #1 is at TDC, the rotor (take the cap off) should point in the general direction of #1 spark plug. If it doesn't, you may be able to fix that. I don't remember if the pin for the drive dog is drilled assymetrically so it will only go in one way, but if it is symetrical, then you should be able to drive the pin out of the distributor dog, turn it 180 deg. and drive the pin back in.

Either way, it's really a moot point if the car runs OK how ever you have it.
 
I appreciate all the input. I will do some double and triple checking for my own knowledge, but the engine seems to run great with the distributor in this position, so I think I'll leave well enough alone. I would like to figure out what is going on with the engine timing though. I'll check it more today and let you know.
thanks
 
If everything is set up correctly and the #1 piston is at top dead center with both the rocckers showing clearance, this means the valves are closed. Because there are two times when each piston will be at TDC, you have to make sure which one you have. Then with the distributor cap off, the rotor should aim to the sparkplug hole for cylinder #1.
 
martx-5 said:
When the timing marks show TDC, both #1 and #4 pistons are at TDC, but only one of them will have the valves closed ready to fire. If you turn the crank 180 deg., the vavles on the other cylinder will close. You'd have to take the valve cover off to see which set of valves are closed. Also, I believe the dog on the distributor can be installed 180 deg out. When #1 is at TDC, the rotor (take the cap off) should point in the general direction of #1 spark plug. If it doesn't, you may be able to fix that. I don't remember if the pin for the drive dog is drilled assymetrically so it will only go in one way, but if it is symetrical, then you should be able to drive the pin out of the distributor dog, turn it 180 deg. and drive the pin back in.

Either way, it's really a moot point if the car runs OK how ever you have it.
Click to expand...

eeep! PSST!! Art! 180° sets #2 & #4 to TDC.

360° is what ya MEANT, I know. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif

And too right about the last remark. Using the timing light on the #1 plug (even if the dizzy ~IS~ 180° out) will allow timing the spark (assuming the damper & TDC mark is correctly positioned with relation to the crank!).
As long as it runs, dizzy position don't mean a thing.
 
DUH...Thanks for catching that DOC. It was early in the morning and I only had one cup of coffee...sorry about that. /bcforum/images/%%GRAEMLIN_URL%%/wall.gif
 
Still a quart low, then! /bcforum/images/%%GRAEMLIN_URL%%/jester.gif
 
I have almost the same story.When I bought the TR3 it was only running on one cly. The PO had hundreds of dollars in receipts where a mechinic had tried to get it to run. Finally he had given up and decided to sell the car. The body was in good shape so I decided to buy it anyway thinking it would be a project. When I got home and started testing everything looked right. Good compression the started turned it fast enough with the plugs out so have oil pressure and it was getting fuel. The dist. looked like it was in right but just wouldn't fire at the right time. I started taking it apart and found that the cam was 180 degrees out of time and the distributer gear was one tooth off. I finally got everything lined up right and put back together hit the start button and it fired right up. So much for my project. I've been driving it almost every day for five years and have yet to touch the engine again. The transmisson, steering and rear is another story.
 
bluemiata90 said:
...the engine seems to run great with the distributor in this position, so I think I'll leave well enough alone...
Click to expand...

Can't blame you for not wanting to mess with it now... but someday it will bug you enough to fix it. For one thing, the igniton wires lay out so very neatly when the distributor is correctly oriented (an the wires trimmed to proper length) just like in the owners manual. Also makes the timing procedure,etc just like the manual.

Really very simple to correct (I had to do mine when I got it). Only tricky bit is getting a feel for the position the shaft needs to be in to allow for the slight twist it does as it engages that (helical?) gear on the camshaft. But that's really a matter of trial & error until you like how it looks.
 
/bcforum/images/%%GRAEMLIN_URL%%/iagree.gif------Keoke
 
This kind of makes me wonder... I have never been able to get my 8 timed with the timing marks on the harmonic balancer, is is about 1/4 turn out... would like to blame it on the PO but I rebuilt it myself so I would have to take credit if that is what is wrong. I have to get Cylinder #1 TDC and make the balancer and go that way... tough to do it that way
 
This is how it looks on a late TR3A.
 

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Crypty's TR6 dizzy has that similar offset
angle and the dizzy works just great.

dizzy22nov.jpg
 
Let's not get into THAT project again....

Dale, I was very happy for you to get the timing advanced properly and the car running well and especially for David to give it his blessing.
 
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