Cam plug, pop and leak

big_bran

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May 28, 2012
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Ok, background mods etc first.
97 cummins 12v 180p 4ks 5x14 he351 over s475 75/83/1.10 20 over cummins pistons stock cam all this in a 99 f250 4x4.
Finally got it back together Wednesday! Started it up and after 45 secs running oil started dropping of bellhousing. Inspectin plate was still off and I was entirely sure it was cam plug. Pulled the trans and adapter, can see that the oil had come out around that plug, or it was collecting in there. Either way ,smacked it a couple more times with a socket gobbed silicone on it, and the adapter plate. Bolted it back up and let it sit over night.
Bolted trans back up. Started her up. Idle seemed to be about 300 Rpms lower which was a good thing, brought the engine up in rpm. Let in run about 1800 for 5 minutes. NO oil leak!
Well today ran motor for a bit and took it out for its first test drive.. Got out of the parking lot and half way down the street. Started to get into it a little bit and heard a pop.. Pretty loud pop! Got the truck stopped hopped out, looked under and that same oil leak is back, literally running out of the adapter.
Babied the truck back to the shop. It looks like tht same oil leak for sure..
I decided to start the motor again and see what in the world that pop could have been.. The idle dropped again to 400! Up to about 1200 rpm the engine runs smooth any higher than that it goes to coughing and popping.

Here's my thoughts, and would love to hear yours. It sound like the popping was timing slip. Btw timing was set at 20.5. I'm thing that was the pop and the idle change/ coughing and hacking. I think that could have put just enough bind on the cam to push the plug out again!

What's your thoughts?

I am really hoping I didn't break a camshaft, but I guess if I did its time to get a Hamilton anyways. Where would u start?! I'm gonna take a day or two break out of frustration. But hitting it hard Tuesday or Wednesday.

I'm thinking oil drain plug see if we have any metal, pull the trans again, pull valve covers make sure the push rods don't look like they are outta wack, and pull the front cover, check the timing and inspect the cam gear for walking!

Could really use some advice, trucks pretty close to sitting on the railroad tracks.
 
The more I think about it I'm sure the timing slipped.. The pop could have been the gear coming loose in there. I'm gonna check push rods and order a new plug. Is there anything else other than the rear main, head, and the cam follower that could be leaking back there? I Checked all of the above.
 
There was a thread a couple weeks ago on this.
That plug can't get pushed out unless something is funky with the cam and gear.
Sounds like a tear it down and prolly a bolt on retainer is in store. Best of luck to ya.
 
There was a thread a couple weeks ago on this.
That plug can't get pushed out unless something is funky with the cam and gear.
Sounds like a tear it down and prolly a bolt on retainer is in store. Best of luck to ya.

I will check that out for sure. when I originally installed the plug I did not put silicone in there. after talking with my cummins tech once that plug has had oil go past it it is going to be hard to stop that leak without pulling and reinstalling properly. I am going to pull the front cover to inspect. I highly doubt there is anything wrong with the cam or the gear. I don't think its pushing out. I think it was just flat out improper installation on my part.

my tech is going to pop it in there for me this time as I am pretty damn frustrated with it. im going to tear it down tonight just to verify there is nothing wrong with the cam.

I back tracked my test drive this morning and the oil leak actually started half mile before the pop.

any other advice on the pump gear. brake clean on shaft and gear. torque to 155 instead of 145?
:bang
 
they pop pretty loud in the press when you are getting the gear off. I have never had one slip in the engine but might be the sound you heard.
 
I know the pump gear sure pops when ur taking it off.. But with the nut and washer there I'm not sure it should pop quite that loud.
 
This is what happened to the cam in the car a couple years ago:

000_0005.jpg


000_0004.jpg


000_0006-1.jpg


We didn't get to the point the plug popped out or the key popped out but the cam gear was rubbing on the front cover.

As far as if the timing slipped and preventing it, I always sand the pump gear and pump shaft with 80 grit when I have one off or the first time timing a truck.
 
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This is what happened to the cam in the car a couple years ago:

000_0005.jpg


000_0004.jpg


000_0006-1.jpg


We didn't get to the point the plug popped out or the key popped out but the cam gear was rubbing on the front cover.

As far as if the timing slipped and preventing it, I always sand the pump gear and pump shaft with 80 grit when I have one off or the first time timing a truck.

Sorry that happened to you bud. Hopefully I am not looking at the same thing.

Question for you guys.

If the cam gear slipped what is your recommendation?

probably use a little emery cloth on the shaft this time.
 
Sorry that happened to you bud. Hopefully I am not looking at the same thing.

Question for you guys.

If the cam gear slipped what is your recommendation?

probably use a little emery cloth on the shaft this time.



heat the gear, slip it on all the way, bolt on a retainer or tig it. It'll never happen again.
 
I did not specify pump or cam gear in my post. But was fully meaning cam gear as refrenced by the "press".
The pictures above are what I am talking about.
Do let us know what you find. Hope the best for ya.
 
Sorry that happened to you bud. Hopefully I am not looking at the same thing.

Question for you guys.

If the cam gear slipped what is your recommendation?

probably use a little emery cloth on the shaft this time.

If the cam gear is walking and you don't want to pull the cam. Then you'll need to drill and tap them end of the cam, install a hardened stud and use that along with a steel plate and spacer to press the gear back on the cam. Once you've got it back on, then weld it or install a retainer on it.

If you're OK with pulling the cam to fix it, then follow the Cummins manual.
 
If the cam gear is walking and you don't want to pull the cam. Then you'll need to drill and tap them end of the cam, install a hardened stud and use that along with a steel plate and spacer to press the gear back on the cam. Once you've got it back on, then weld it or install a retainer on it.

If you're OK with pulling the cam to fix it, then follow the Cummins manual.

Pulling the cam is not a huge deal, I have had it out who knows how many times.. enough that it sure should be a Hamilton.

But you would actually weld the gear to the cam?
 
Well tore it down tonight. the plug was not pushed out. after pulling the plug there is absolutely no sign of cam running on it or pushing into it.
tore the front cover off, the cam has not walked an inch. timing definately slipped the gear was on the pump but after half turn or so with my puller it popped right off..
I did blow a cac boot, very possibly that was the pop.

after really really looking at it i found the bottom corner of the cam follower plate gasket was cracked, you can se that oil was either running from the cam plug to the bottom of it and down or the gasket was leaking. went about installing a new gasket. got the pump about half way reinstalled and called it a night.

I am still convinced the cam plug was leaking. It looks like i was wrong and did way to much work for nothing (pulling the trans several times) oh well insurance. so tommorow its finsih the install of pump, timing reinstall trans and front end, and maybe get a test drive in.
 
oops.

Well tore it down tonight. the plug was not pushed out. after pulling the plug there is absolutely no sign of cam running on it or pushing into it.
tore the front cover off, the cam has not walked an inch. timing definately slipped the gear was on the pump but after half turn or so with my puller it popped right off..
I did blow a cac boot, very possibly that was the pop.

after really really looking at it i found the bottom corner of the cam follower plate gasket was cracked, you can se that oil was either running from the cam plug to the bottom of it and down or the gasket was leaking. went about installing a new gasket. got the pump about half way reinstalled and called it a night.

I am still convinced the cam plug was leaking. It looks like i was wrong and did way to much work for nothing (pulling the trans several times) oh well insurance. so tommorow its finsih the install of pump, timing reinstall trans and front end, and maybe get a test drive in.

I hate it when that whole "way to much work for nothing" happens.. Tuition is what I call it. Did ya get it all back together?
 
just now noticed you are in AZ. where are you at? and if you are in a bind gimme a call. 520 510 6020 Casa grande
 
I'm up in Holbrook! a bit out of the way for ya! I think I am in good shape. other than I messed up the threads on the end of my pump last night.
 
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