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timing sprocket off, issues with driving it?

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R

recordsj

Jedi Warrior
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I have a '75 1500 mg midget.
I believe my timing sprockets are not where they should be. To allow the car to run (have any kind of power) I have to set the timing with the distributor to around 25 deg BTDC. It may be a while before I can get into the engine to fix the timing sprockets. I don't know how long it has been like this since it was like this from the previous owner. Is there any issue of keeping it this way and driving it until I have time to fix it? I have noticed I get low economy @ around 23MPG.

By the way I have already replaced the distributor with a new one with electronic ignition, also changed out the rotor, cap, wires & spark plugs. I still had this issue even before making these changes, which needed to be done anyways.
 
Apparently since it's been running so long with this problem, that the only issues are poor mileage and poor power. There's always the possibility of bending a valve when over-revving, but since it hasn't happened, it probably wont. Go ahead and fix it as soon as possible. It will give you much more driving pleasure for less gas money.
 
The issue may be with your distributor. Perhaps something is gumming up the works and not allowing it to advance properly. That would certainly cause the symptoms you speak of... and would be helped by your solution.


Nial has a neat way of checking the timing on the cam without pulling the front cover, but I can't remember it right now.
 
do you have some contact info on getting ahold of Nial to get this method of checking timing on the cam without pulling the front cover?
 
I have already replaced the distributor with a new one that also has electronic ignition and the problem is still there.
Old one was a 25d4, new one is a 45d4.
 
Here is the method Nial explained to me (hopefully he will be along soon to point out any errors I have made):

First, set the valve clearance for #7 and #8 valve to .08"

Next, set the motor at TDC for #1 piston and check the valve clearance for #7 and #8 valve. The clearances should be the same. If they are off, your cam is out of time.
 
Gesh, that would work. Never would have thought of that.

Nice.
 
I should think 7 and 8 closed. ie lifters all the way up, both of them.
 
When #1 valve is fully open set the clearance for 8. When #2 valve is fully open set the clearance for 7.

Don't forget to set the clearance back to factory spec when you are done.
 
The above works only if the cam is ground for "split" overlap timing. Don't know if your cam has split overlap or is one with non symetrical timing. The cam specs should show the intended timing at TDC overlap. Top of the exhaust stroke. Intake valve opening vs exhaust valve closing.
D
 
Hello all,

another way of saying what position the engine is in, No 1 TDC firing (fired normally), no 4 'rocking'..

It is a quick and simple check, as Dave says for symmetrical cams. My Triumph 2000 (Official) workshop manual has that method in it.

Alec
 
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