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Discussion Starter · #1 ·
I have recentley purchased a 91 Somona, I am trying to set the timing. And am sorry if it is here but I can not find it using the search function.

I have found and disconnected the brown and yellow wire under the dash, And installed the new dizzy cap and button.

I then purchased the timing gun, and read all its instruction. So what am I missing?

I may be very dumb, but I cant for the life of me find the timing marks. First I need to get the engine to TDC on cylinder number one to set the base timing.

How do I set the base timing? As in find the mark...

And then on wich pully is the timing mark and pointer.

Thank you so very much for helping me out in anticipation
 

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Discussion Starter · #2 ·
Still struggling finding the timing marks, but I go the olde girl running, and set the timing up by ear.

I even went and bought a chiltern repair manual which is about as much use as an ashtray on a motorbike!

I am almost certain the timing mark should be on the crankshaft pulley, And I should have a pointer close by. Well I have looked and looked and looked again and it isn't there. Is there another way I can set the timing?

Again its the 4.3, 6 pot.

cheers
 

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The mark should be on the crank pulley. Inspect 360 degrees around the OD of the pulley. You may need to 'bump' the starter to get the crank to turn a little bit at a time so you can inspect all the way around the pulley. If there is no mark, then I don't know what to tell you. If by some unusual chance there is some unique way to set the timing on this truck, hopefully one of the techs will chime in.

If you do find the mark, there should be an emissions label on the radiator support or on the underside of the hood. That label will tell you exactly what to set the timing at.
 

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If the engine is running

You stick the timing light to cyl #1 sparkplug wire... now it will be flashing. Point it around the crank pulley and you should see a line that appears stationary. This line should line up with a mark. Just twist the distributor to shift the line to one mark or the other.

It's hard to find that is sure so look carefully. If you can find the line on the pulley you may wish to put liquid paper on the line to make it stand out.



 

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it hasnt by chance had a newer engine installed with a plastic front cover,there are no marks on it only a kind of v groove.timing is set to 0 with tan and black wire disconnected to put timing into est bypass.hook up lite and line up groove if has plastic cover if not look on left side of cover looking at it or try straight down between w/ pump.its been awhile since I worked on anything that old,generally 1 to 3 year old stuff.
 
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