How do you find TDC Compression stroke?

[Adrian87]

The only method I've found is to have your finger in the #1 plug hole, and hand crank the engine until it blows your finger out. Well with only 2 hands this is impossible to do, so I'm wondering if there's another way to do this. I see a notch in the balancer, when this meets zero on the marker we're at TDC, right? Just don't know which stroke, right?

 

[87GNSteve]

Do you have the valve covers off?
or do you have after market covers?

I have aftermartket covers with the oil hole over by the # 1 rockers.
I put a long screw driver on the rocker and turned the motor, when the screw driver dropped as i approached TDC I knew it WASNT the compression stroke.

 

[Adrian87]

I have aftermarket covers, but the oil hole isn't on #1.

 

[87GNSteve]

Well unless you can find some one to stick their finger in the hole, removing the valve cover is the next best.

maybe if you have a rubber or foam stopper or something that will fit and "Pop" out that might work but i didnt have anything.

 

[excobraguy]

Wooden dowell pin works great too!

 

[TurboTR]

Well you hand crank it with a socket wrench on the crank snout Have all the plugs out, and all quite doable by only 1 person while leaning over the ds fender And the finger just has to be over the plug hole, not actually down in it. It's quite a noticeable difference between TDC compression (blowing hard as the piston comes up) vs TDC overlap (no blowing at all).

TurboTR

 

[Blown&Injected]

Well you hand crank it with a socket wrench on the crank snout Have all the plugs out, and all quite doable by only 1 person while leaning over the ds fender And the finger just has to be over the plug hole, not actually down in it. It's quite a noticeable difference between TDC compression (blowing hard as the piston comes up) vs TDC overlap (no blowing at all).

TurboTR

Agreed

Your finger does not need to be in there all the time just a bit before the balancer mark comes around - Clockwise

 

[1986TR]

i usualy hook up my compression tester hose with out schrader valve in it and put youre thumb on hose end.....the way my compresion tester is designed makes this easy...also once you feel compresion just rotate to mark on crank youare at TDC compression stroke:biggrin:

 

[counterman]

I just did this. I had a compression tester air hose that you can get at any parts store. I took a kid's balloon and put it over the open end of the hose and taped around it's base to ward off any leaks. I screwed the test hose into the no. 1 spark plug hole. I used the crank bolt and a breaker bar to spin the motor over by hand. On the overlap stroke, you get no action with the balloon. However, on the compression stroke, the balloon will inflate to the size of a baseball as you approach tdc. No problem at all telling where you are. Perfect if you are working by yourself. I only pulled no. 1 plug, and was able to rotate the motor with little trouble with the breaker bar. You could do the same thing by bumping the starter if you wanted to. Give it a try. Counterman.

 

[gnxtc2]

I use the Whistler from S&G Tool Aid, part # 33650, page 12 http://www.toolaid.com/catalog.pdf

-Remove #1 spark plug
-Screw in The Whistler by hand
-Turn motor over by hand
-The Whistler is going to whistle on the compression stroke
-Stop turning when balancer is on "0"

Billy T.
gnxtc2@aol.com

 

[Adrian87]

Excellent information, guys. Thank you very much. It may be next weekend before I can get back to work, but this should get me there. Thanks!