front cam cap cracked--help!!

[Roush05]

I'm typing this in a hurry so forgive any mistakes.

I have some FRPP Hot Rod Cams that myself and a buddy were putting in tonight. We were almost done with the driver side cam when I noticed that the front cam cap was cracked. We didn't notice it up until just now, but we don't think we did it while we were working on the cam swap. Pics are below. What should I do? Can I replace it with a new cap or do I have any other options? Also, does anyone know what part number this is?

 

[erat]

Trip to the cam cap store.

 

[Mustang30212]

Those are machined like main caps in the bottom end. If you replace the cap you will need to have the cam journals align honed. I had to replace the main cap on a block once and this was the only option I had other than replacing the block.

RH

 

[Roush05]

Those are machined like main caps in the bottom end. If you replace the cap you will need to have the cam journals align honed. I had to replace the main cap on a block once and this was the only option I had other than replacing the block.

RH

What if I went to a junkyard and got a cap from another 4.6 3V? Would that work? What exactly do you mean by 'have the cam journals align honed'?

 

[S197gt07]

do you have any machine shops around man?

 

[Roush05]

Not that I know of.


edit: google maps says there are a couple.



EDIT: Would one from a junk yard work though? I am trying to decide where I should go first.

 

[crownaviation]

Go take two circles of equal size. Cut them both in half. Now try to make a perfect circle by switching them out. Your car was (or should have been) align honed with the original caps in their correct direction from the factory. The tolerance is close. That is why on the early heads they were numbered and had arrows stamped in them to dictate direction for assembly.

Align honing is a process to make sure the centerline of the camshaft towers are straight, round and free of taper (will prevent binding/excessive wear etc). It also helps to ensure it is parallel to the crank etc.. Basically in your case, you should check (replacement cap) to make sure there is a perfect circle when torqued correcltly. You dont want to be able to feel any areas that have a step in/out or tilted when assembled. The cap should also be the same radius (the two circles thing). The only guarantee is to have it honed. Granted Ford does a good job when the parts are spit out of the machine, but think about all the variables here. Again this is why they are still align honed when assembled. BTW,,, there is not much if any material that can be removed from the caps per the manufacturer/prominent 4.6 builders. Some get away with it evidently but have not tried it.

Just a question, did you remove that cap before you removed the other cam caps? Did you use a rubber mallet or such to tap the cap loose when removing or did you use the cam as a lever? There is a good bit of pressure from the springs when you remove the other caps. Looks like it may have had a load applied to it when it was bolted down. Have not seen one damaged like that before.

I, unfortunately, have a cap you can have from a set of heads that did not pan out. You pay the shipping and I can have it out in the morning for free. I doubt any junk yard will let you walk out the door with just one cap... I will not guarantee you it will just bolt on and be fine. This is where the honing will give you sleep at night. In my case, from the FACTORY I have a cap that was installed backwards on the breakin. It was evidently turned back around at the factory (and was honed with it backwards from them). For grins, we installed it the way it was supposed to be and the cam was locked up when the cap was torqued. It lasted 4000 miles and even with the bad pic (too much light) you can still see the metal that it made in the cam tower. The cam is much worse than it looks in the pic. It also started to move metal out of the cap (you can see some was pushed out of the side). Might have gone a little longer but we discovered it when we removed it. The cam is likely ruined but wont spend the money to clean it up and try it (stock cam).

http://i1138.photobucket.com/albums/n526/crownaviation/2012-05-10131233.jpg

http://i1138.photobucket.com/albums/n526/crownaviation/2012-05-10131226.jpg
PM me if you need one.

 

[PNR Welding]

Thats gonna need a align hone, and head will probably need to come off to do it. Not sure if u can get that hone in there in the car. You cant just replace the cap with another. Ur cam will get wiped. Ur other option might be to polish that lobe down enough that it makes clearance, wrong way but might work.


Sent from my iPhone using Tapatalk

 

[crownaviation]

Thats gonna need a align hone, and head will probably need to come off to do it. Not sure if u can get that hone in there in the car. You cant just replace the cap with another. Ur cam will get wiped. Ur other option might be to polish that lobe down enough that it makes clearance, wrong way but might work.


Sent from my iPhone using Tapatalk

^^^ this

 

[toorbeenee]

^^^ this

+1 you will need to take the heads off

 

[BruceH]

You have two options. I've have caps from different heads line up, so have others. It's worth a try. Whatever the process is that Ford uses to ream those caps it's damn good.

The same thing that happened to you has happened to others on this board. It happened when I was helping a friend install hot rods last year. We were able to use a cap I had left over from a set of junk heads. The joining edges felt smooth, we plasigauged the journal and it was within the Ford spec.

The other is to have it welded. Not many welders will be able to do it but it can be done. Just don't loose the cracked piece.

 

[BruceH]

I'm typing this in a hurry so forgive any mistakes.

I have some FRPP Hot Rod Cams that myself and a buddy were putting in tonight. We were almost done with the driver side cam when I noticed that the front cam cap was cracked. We didn't notice it up until just now, but we don't think we did it while we were working on the cam swap. Pics are below. What should I do? Can I replace it with a new cap or do I have any other options? Also, does anyone know what part number this is?

It happened while you were tightening the caps down. This can happen if the followers with load on them aren't taken out during the install. Spring tension results in a misalignment of the cam and retainer cap. You can't tell anything is wrong because of the spring tension that has to be overcome when tightening the caps.

 

[Roush05]

It happened while you were tightening the caps down. This can happen if the followers with load on them aren't taken out during the install. Spring tension results in a misalignment of the cam and retainer cap. You can't tell anything is wrong because of the spring tension that has to be overcome when tightening the caps.

... son of a bitch. I was off eating while they took the stock cam out, and now that I think about it I think that all the followers were in there while we were putting the aftermarket one in.

I'm gonna try to find a welder first. I know a couple good ones, so that may save me a ton of trouble.

 

[JeremyH]

That first cap is the thrust cap that groove holds the cam in place foward to aft. As you have found out they can break, my thoughts on why. Did you have the cam clocked properly to relieve most of the pressure for the install. That and did you slowly and evenly undo on the cam cap bolts or were you taking off one at a time? Best of luck hope its an easy fix in the end!

 

[S197gt07]

... son of a bitch. I was off eating while they took the stock cam out, and now that I think about it I think that all the followers were in there while we were putting the aftermarket one in.

I'm gonna try to find a welder first. I know a couple good ones, so that may save me a ton of trouble.

I told you to watch man!

Tell your friend its 100% his fault if he didnt take those 3 followers out like we had talked about. Hope you can find a welder.

 

[Roush05]

That first cap is the thrust cap that groove holds the cam in place foward to aft. As you have found out they can break, my thoughts on why. Did you have the cam clocked properly to relieve most of the pressure for the install. That and did you slowly and evenly undo on the cam cap bolts or were you taking off one at a time? Best of luck hope its an easy fix in the end!

I think that he put the three followers back on after taking the stock cam off.

Thanks man, I am banking on it.

I told you to watch man!

Tell your friend its 100% his fault if he didnt take those 3 followers out like we had talked about. Hope you can find a welder.

I just found a welder and I'm going to be paying out the ass for him to come in on a holiday weekend to fix it but I should have it back by 1 or 2. Thanks a ton crown by the way. I plan on getting this one welded and sticking it on there for a couple days until the cap that crown sends me gets in. Then I'll get it machined and swap them out.

 

[Agent007]

You can't just get it machined and swap them out... you have to remove the affected head and take it to a machine shope to get it align honed. The cam will have to be removed as well as the followers... possibly even some lash adjusters, not sure. Good luck!

 

[Roush05]

Well then my next set of questions.

-Will a welded cam cap be a permanent fix?

-Why can't you use the specs of the cracked cap to machine the new cap as opposed to pulling the head?

 

[BruceH]

I think that he put the three followers back on after taking the stock cam off.

Thanks man, I am banking on it.

I just found a welder and I'm going to be paying out the ass for him to come in on a holiday weekend to fix it but I should have it back by 1 or 2. Thanks a ton crown by the way. I plan on getting this one welded and sticking it on there for a couple days until the cap that crown sends me gets in. Then I'll get it machined and swap them out.

IMO the weld will be stronger than the cast material. Do what you want but I don't think you will gain anything by swapping it out.

The welder will know if he can do it or not. Hopefully he can.

When I said it happened to a friend I was helping it was just that, I was doing most of the install and was the guilty party. We weren't using a spring compressor and I was fairly complacent since the first cam went in with no issues. It was caught earlier in the breaking point than yours. We tried using the cracked cap but it didn't hold. Luckily the spare cap I had worked great. He drove the car almost a year after that with no ill effects. Now he has a 2013.

 

[Roush05]

IMO the weld will be stronger than the cast material. Do what you want but I don't think you will gain anything by swapping it out.

The welder will know if he can do it or not. Hopefully he can.

When I said it happened to a friend I was helping it was just that, I was doing most of the install and was the guilty party. We weren't using a spring compressor and I was fairly complacent since the first cam went in with no issues. It was caught earlier in the breaking point than yours. We tried using the cracked cap but it didn't hold. Luckily the spare cap I had worked great. He drove the car almost a year after that with no ill effects. Now he has a 2013.

Good to know. Did you machine your spare cap?