A Potential Shortcut for Removing And Installing PT Camshafts

[Handy_Cruiser]

While installing new timing belt components and my new NS1PT performance camshafts, I figured out that I could put my own marks on the timing belt and sprockets. This made installation easier and faster.

Later I got another idea. There's been lots of members with good timing belts that have had to replace blown head gaskets. The head removal calls for removing the timing belt whether it needs to be replaced or not.

Below is JUST AN IDEA. I have not completed it on a running PT. This is just an exercise in how this might be done. The advantage to trying this is that if someone cannot finish it, they are likely no worse off than if they just did the job the traditional way. But only try this at your own risk.

On this salvage 2003 NA PT engine, I attempted to remove the camshaft in a way where I did not have to remove the timing components. And I believe I could likely get to all back together and in time the same way. This would cut many hours off of a head removal and replacement job.



1. First, position the engine at DTC. You can do this with a dial gauge. Or just judge when #1 piston is all the way up on the compression stroke.


2. Place marks on each cam sprocket with adjoining marks on the timing belt. Then put a mark on the lower crank pulley that will indicate where DTC is.


3. The upper timing cover would need to be removed along with the two cam sprocket bolts.


4. Next, take a camshaft loose from the head and raise the left end of the camshaft.




5. With the camshaft raised on the left end, the timing belt is now loose and can be pushed off. And the cam sprocket can be removed.




NOTE: Before trying this on a salvage PT, I was afraid that doing this would damage the camshaft seals. But that does not appear to be the case. The seals have enough room to move when the camshaft is lifted on the left end.




6. Reinstalling the belt would work the same way. Just put the sprocket back on the belt and align your marks. You can hold the loose sprockets on the belt with report binder clips. Then put each camshaft back in at an angle through the timing cover into the cam sprocket. Once both cams are back on the sprockets, tighten the cams back down. And by comparing the timing marks on the cam sprockets, timing belt and crank pulley, you will know if you have gotten everything back in time as it should be.




Here's the deal with trying this. The camshafts can definitely be removed this way without causing damage. If you cannot get the belt back on the sprockets during reassembly, then you will have to take down the right side of the engine just like you would if you were doing this the standard way. So there's very little cost to try this. You will just be working in a very tight space around the cam sprockets.

Again, I have not completed this procedure myself on a running PT. It is just an idea at this point. Do this at your own risk. And make sure you have the tools and skills to get the job done no matter the outcome. But if it does work, it would be a great shortcut for someone that needed to replace a blown head gasket.


PS: I am just putting this out there for comment and conversation. For me, there's a lot of joy in figuring new things out like this. The more information the better.

[rob342]

since camshaft acceptable runout is generally around 0.0008" or less, i would never attempt to pry the belt back on using one like that. i'm kinda picky though. i'd literally throw out the ones by your keyboard because you stored them horizontal instead of standing on end.

[boogeyman]

Hello!
I was wondering if anyone has tried this?
I'm thinking about trying it but I've been advised that getting the timing belt back on would be a difficult if not impossible task unless the tensioner is loosened first.

[mtyson]

I don't think it would work unless the tensioner is removed first... I don't think even having the tensioner in the off-tension position would do it.

[Handy_Cruiser]

Originally Posted by mtyson

I don't think it would work unless the tensioner is removed first... I don't think even having the tensioner in the off-tension position would do it.

I tried it on a PT with the tensioner still in place. The primary issue is going to be keeping the timing belt in position. Since it's going to be behind the timing cover, you won't be able to see anything but the top part. There would be no value in trying this with the tension off the tensioner since you would be about 75% into doing it the regular way in order to access the tensioner.

And like I said in my write up, I've not tried this on a running PT, just a salvage car. So you would have to attempt it as your own risk. But in truth, there's not much risk. The torque on the camshafts is minimal and if you can't make it work, the remedy is to do simply do the job the routine way. If I had a good timing belt and just needed to change the head gasket, I would definitely try this method first. And of course, what might work for me might not be feesable for everyone else. My tolerance for risk and ability to recover from loss is a little higher than some folks.

[rambojoe]

exactly what rob said. and the caps would be destroyed, definitely on reinstallation.. as would the head journals... as would the cam shaft seals. even trying to shortcut some cams out of a junkyard motor- you would be better off just crow barring off the wheels first, but even that would screw up the cam...


please, no more short cut threads. it is not good advice.

[Handy_Cruiser]

Originally Posted by rambojoe

exactly what rob said. and the caps would be destroyed, definitely on reinstallation.. as would the head journals... as would the cam shaft seals. even trying to shortcut some cams out of a junkyard motor- you would be better off just crow barring off the wheels first, but even that would screw up the cam...


please, no more short cut threads. it is not good advice.

Over the years, I've come to really appreciate Rob. I believe Rob has a great deal of what is called "fluid IQ". IQ is made up of two parts. Static IQ is you knowledge based on experience and education. Fluid IQ is your natural ability to see patterns in what you experience and observed. Someone as gifted as Rob can often make valid conclusions off of what others might see as scant data or what appears to be unrelated data.

At my job, I try to surround myself with people like Rob if I can find them. Having an unusually high amount of fluid IQ causes many people, like Rob, to gain a lot of static IQ during their lifetime. This happens to some extent even for people with an average amount of fluid IQ. This is why some really stupid young people mature to become fairly intelligent adults. The down side is that we all lose fluid IQ as we age. So for someone with a career like mine where I basically get paid for my intelligence, it's always good to surround yourself with younger people with lots of fluid IQ. And it's a good idea even here on an internet forum. When Rob gives his opinion, I consider it closely even if I disagree on the face of it. And even when I end up rejecting his opinion, I usually end up learning more myself. I never take Rob's opinions lightly when he's being sincere.

I cannot guess at your fluid IQ. But I value your opinion just the same. And I will continue to post all the shortcuts and other things I am interested in. And as always, your input is welcome.

[NitroPT]

Some short cuts from the factory recommend procedures have some merit to think about but this one about the cams is not one of them. There are way to many human and mechanical as well the "GOD" factor variables that can and most often will go wrong attempting them.

[nj318]

A thought on this, after marking the positions:

Why not losen the sprocket screws as long as the belt is in place, then remove the tension, remove the belt, remove the sprockets, then continue with the procedure as proposed by Todd?

That way, there would not be any unusual tension on the camseals...

[Handy_Cruiser]

Originally Posted by nj318

A thought on this, after marking the positions:

Why not losen the sprocket screws as long as the belt is in place, then remove the tension, remove the belt, remove the sprockets, then continue with the procedure as proposed by Todd?

That way, there would not be any unusual tension on the camseals...

The journals for the cam seals allow the seals to move so there is not much if any tension on the seals while pivoting the camshafts. This was one of my biggest concerns before I tried this on the salvage engine.

As for letting off the tensioner first, it's very difficult to access the tensioner because it's under the timing cover. As you can see in the photo below, removal of the timing cover involves removal of the engine mount.




And that's the hardest part of this job because it involves jacking the engine up pretty high to get at it.




If we have to go that far, we might as well do the job by the standard method.




The magic if trying the method I've described is that it involves none of this. You don't even have to lift or get under the car. It turns a fairly complex 8 to 16 hour job at home into a 1 hour job. The problem doing a job like this to completion is that it's only going to be useful in a few instances such as when you already have a good timing belt but have a blown head gasket or when installing performance camshafts. To be exact, it was while removing and reinstalling my performance cams several times to correct a valve training issue that gave me the idea.




Right now I'm working on a number of home improvement projects. But I have a growing box of parts to detail my PT's engine bay. When and if I do that, I may remove and reinstall the cams just to show it can be safely and done. And maybe I'll do some light performance cams when I do it.

In the meantime, this is just an idea to discuss. The anonymity of the internet sometimes cause more timid people to be argumentative, petty and even cruel. But the exchange of ideas can be a good thing if our skin is thick enough. And everyone's opinion is welcome.