Engine/Transmission (1994 - 1998) Unable to find TDC with Timing Pin

[alaskagrizz]

I have now tried twice to locate TDC with the timing pin on a truck I bought used last year w/ 22K miles. Either watching #1 intake on the intake stroke, or by watching #5 (next in firing order) intake bottom and start up, I still cannot seem to get the pin to "pop" in to the cam gear recess. Can I assume that possibly the fragile plastic pin was sheared prior to me acquiring this beautiful dually, or "is there an easier way" to find that sweet spot, and I am just missing it? I used the alternative method of watching the intake of the next cylinder to fire last night when checking valve adjustment, as well as right after getting it last year. I am also wanting to advance my timing to 15-15. 5 in the near future, and am curious as to how to assure proper pump position without "the pin"? Help here is much appreciated... ... ...

 

[bighammer]

I've heard that the pin is not always mounted in a way that it's truly accurate for TDC. I couldn't get mine to engage either. I used a dropped valve to mark my harmonic balancer. (I posted instructions in this post.

 

[KLockliear]

Pull the pin out and look at it. If it's broke off, that's a major PITA.

 

[Andy Redmond]

You can pry the star washer off, then pull the plug out, if the plug has a good full "point" then remove the o-ring re-insert and see if the alignment is the issue as "bighammer"suggested. The star washer usually needs a few tweaks with the needle nose pliers and I use a 3/8 dr. 1/2" deep socket as a "pusher" to reset the star/toothed washer.



I've had good success with some longer drills and sharp o-ring picks in getting the plastic out of the gear recess. Just spin the drills in your fingers to dislodge the plastic tip...



A Dodge tech once showed me his method, use a "remote" starter (unplug the shutoff solenoid) and hold presure on the pin while the starter was turning the engine over. As he it bumped it near tdc the pin falls in the hole and the engine will usually stop.



Then he uses a prybar or small pliers and dislodges the plug. I then thought he must not work on "his" prior repairs for valve adjustments, timing etc.



However, please don't do this as it usually damages the pin and some poor sap pays me to fix it! Like Keith says its not any fun, even if you get paid!



Sometimes I also will pop the timing pin out on the side of the pump, pull the timing pin and look for the slot to come up. . catch the 3/4 qt of oil and re-fill the pump through the afc before cranking the truck to avoid governor damage until lube oil is circulated from the engine crankcase. .



Good luck

 

[alaskagrizz]

In examining timing pin from beneath vehicle with flashlight and inspection mirror, I see the star washer you are referring to. My question here would be accessibility to actually get at that washer to pry out. The timing pin and mounting boss is attached to back of gearcase w/ 2 small torxbit screws. Can anyone relate whether it is possible to remove those two screws, and just remove pin and mounting boss intact as an assembly? If possible, I think that would be preferable..... since access with arm from under intake piping is blind (by feel only). At least you could get on those screws w/ proper bit. Any input here is much appreciated! Thanks guys... ...

 

[Howard Durand]

It is my understanding that the timing pin assembly is movable laterally once the two screws are loosened. That allows the manufacturer to set the engine to true TDC then install the pin assembly to match.

If you remove it, you will have to find TDC by the drop valve method then reinstall the pin.

 

[chrleb1]

I know that this is probably too much work, but i use a dial indicator in the #1 injector whole and find TDC with the piston. Really no guessing about it, the only thing you have to check is what stroke it is on. Usually very close.

 

[HEMI®Dart]

I have had poor luck getting the pin to engage. It's tightly tolerenced to the hole. I got it to in lock in once. Luckily I marked the balancer w/ Wite-out. I was blue in the face a few times trying to get it in. I knew I had to be close by looking at the marked balancer and the #1 cylinder valves. Still No Go.

 

[bighammer]

Originally posted by chrleb1

I know that this is probably too much work, but i use a dial indicator in the #1 injector whole and find TDC with the piston. Really no guessing about it, the only thing you have to check is what stroke it is on. Usually very close.

I'm not sure that's as easy or accurate as dropping a valve. Maybe if you're removing the lines anyway and have an extra injector washer and dust seal... .



I like the positive stop of the valve interference. You get 2 marks and split the difference. I suppose if you did the same thing with the dial indicator (reading near the top instead of at the top and splitting the 2 marks) it might be OK.

 

[Briar Hopper]

On a few trucks, I found the plastic pin to be so tight as to not move at all... . I hit the 'ol LeBlond Makino shop lathe, and machined a replacement from steel, the tip is the same, even the same taper on the shoulders, the body is longer and is an exact fit in the gear case hole, and has grooves for a secure grip. (I hate knurled grips on anything)

You need to have your mind on your work if you use a steel pin like this, you don't need to forget and leave the steel pin in there, and bar the engine over.....

I don't use it on every truck... just the ones with a million miles and a virgin pump... .

 

[WDaniels]

alaskagrizz,

The pin that locates the hole in the injector pump gear is smaller in diameter than the hole in the gear. Piers told me that the pin only gets you real close but it still can be off by up to 3 degrees. His words not mine. He said that the only sure way to find exact TDC is to use the method as described in the shop manual.

WD

 

[onestackdram]

ok this is really simple. LEAVE THE PIN ALONE IT IS NOT WORTH A DARN. to find TDC on cyl. 1 pull valve covers on #1 and #6 while watching #6 turn the engine over in its proper rotation. Watch for #6 exhaust to 'start' closing then slow your rotation down. Now you are watching for the ex. to JUST close and the intake to just START or just rock open. Then you are at TDC #1.



to find TDC on any vehicle you need to watch its companion cylinder not the next in firing order.



on our 5. 9 it works like this



1 - 6



2 -4



3 -5



firing order 1-5-3-6-2-4



*hint* to remember this 15 will get you 36 years parole in 24... lol



Russell

 

[bighammer]

Originally posted by onestackdram

ok this is really simple. LEAVE THE PIN ALONE IT IS NOT WORTH A DARN. to find TDC on cyl. 1 pull valve covers on #1 and #6 while watching #6 turn the engine over in its proper rotation. Watch for #6 exhaust to 'start' closing then slow your rotation down. Now you are watching for the ex. to JUST close and the intake to just START or just rock open. Then you are at TDC #1.



to find TDC on any vehicle you need to watch its companion cylinder not the next in firing order.



on our 5. 9 it works like this



1 - 6



2 -4



3 -5



firing order 1-5-3-6-2-4



*hint* to remember this 15 will get you 36 years parole in 24... lol



Russell

Russel,

I had thought about trying to do it that way but because of the "overlap" of the intake and exhaust valve movement, I couldn't figure the exact center between them. A bit tough to get a dial indicator on the #6 valves to detect movement.

 

[onestackdram]

you can see it with the naked eye, you dont need a valve indicator. what works even better is if you have a friend there that can put his fingers on the valves of number 6 so that he can feel it start to rock.



Russell

 

[ndurbin]

I've never used the pin. Always used vavle overlap and a dial indicator. It's really easy if ya have the special socket that goes in the hole and a long extenstion.



easy to remeber too once ya got everything down.

 

[24VChev]

Valve Rock

I always use the "valve rock" method for valve set but I don't think it would be accurate enough for a pump timing adjustment. I would either use a dial indicator on the pistion or the valve drop method. I have also made up a pistion stop wich works like the valve drop method. It is a tool that fits in the #1 injector hole. It stops the pistion and the you make a mark of the balancer. Turn the engine back about 180* then make a second mark. Split the two and you have TDC#1.



I thought that the companion cylinders for the 6 cylinder are



1-6

2-5

3-4



just split the firing order in half for any engine and you can find the companion cylinder:





153

624





Malcom

 

[bighammer]

Originally posted by onestackdram

... have a friend there that can put his fingers on the valves of number 6 so that he can feel it start to rock.



Russell

HIS? HE? I think I see an oportunity for the attractive female friend to lend a hand. Get her up and bent over with hands on the #6 valves.....



Jeez Russel, you're on to something here. Throw away the tools! I need an assistant in the shop. Oo.

 

[Scot]

If the tit is broken off, use a hot 3/32 welding rod or coat hanger to get it out. Let it melt in and harden. Comes right out. You can pull the plunger and star washer w/o loosing factory setting.