Fix Camshaft Journals?

[turbodaytona87]

The camshaft journals of my head are in pretty bad shape. I still get 12psi of oil pressure, hot idle, but wanted to see if there is a way to clean up the journals while I'm fixing another engine issue. I would just go find a good head in a junkyard or from one of the local guys, but mine is ported. Is there anyway to repair cam journals?

[shelbymonster]

i got one head that is like your , id like to see the fix options

[4 l-bodies]

Back when these heads were numerous and in current production, some machine shops would actually fit the cam journals with a set of bearing inserts. Think of a rod bearing. This was an expensive fix at the machine shop. I actually have one of these heads. Bought it more out of curiosity than anything. It needs new seats, so it just sits in the garage. You will not find many machine shops that have the ability to alignbore and hone camshaft journals, let alone have the equipment to cut the tangs for bearing retention.
The factories fix for this problem was they had camshafts made that were oversize. "OSJ" stampings were on these heads. These would obviously be a bad choice for porting since camshaft choices would be limited.
Where there is a will there is a way to fix your cylinder head, but I surmise you could easily exceed the cost of your porting repairing this. Usually torn up cam journals are the result of glass bead or foreign material that wasn't cleaned out of oil galley while the head was being overhauled. I always pop the oil plugs out and run brush thru any head I'm porting.
Todd

[turbodaytona87]

I'm guessing my scoring is from the couple of oil pressure mishaps I had. Couldn't a machine shop align hone a head like they do a block?

[supercrackerbox]

Call Spanel and see what they say. I think they're the most likely to have that equipment.

Let me know what you find out, because I have an extra head on the shelf, but misplaced the cam caps, so I would likely have to have the same thing done if I put some other caps on.

[Directconnection]

You can line bore them, but it's not cost effective. We have a simple line bore fixture for ohc heads... I hate it as it's ghetto, but it does work. We also have a big line bore for doing blocks.... All I can say is that you take sandpaper by hand (light grit) to take heavy scratches/grooves down. This will open up your clearances more... but then if you have a dial bore gauge only... you can see how round they are. If you had too much clearance, then you could cut the caps just a sliver (like .001-.002") and then measure afterwards. Now, the bores might be (should be) egg shaped, and if you have a good dial bore gauge, and lots of patience, then you could sand the *tight* areas of the cap to make it back to round.

It's a lot of finnesse....

[karlak]

Dont see why this would be a costly repair. V8s get align bored and cam bearings installed all the time. The hard part would be finding a bearing that would work.

[turbodaytona87]

Call Spanel and see what they say. I think they're the most likely to have that equipment.

Let me know what you find out, because I have an extra head on the shelf, but misplaced the cam caps, so I would likely have to have the same thing done if I put some other caps on.

Can do, but it probably won't be until I take the engine apart.

[turbovanman²]

Dont see why this would be a costly repair. V8s get align bored and cam bearings installed all the time. The hard part would be finding a bearing that would work.

These aren't V8's,

Seriously though, 4 cylinder stuff seems to be harder to repair, I would look into just doing a line bore or minor cleanup.

[MR. X]

The larger diameter boring bar does not deflect like the one needed for our cam journals due to length. Also the smaller bar will most likely chatter. I think the cost would be prohibitive. I do have the bearings for this fix because I also have a nice ported head with cam bore damage. Here is an article laying out the prices for the specialized equipment.

http://www.enginebuildermag.com/Arti...g_subject.aspx

[Directconnection]

Dont see why this would be a costly repair. V8s get align bored and cam bearings installed all the time. The hard part would be finding a bearing that would work.

Ever do one?

V-8's don't have their cam tunnel line bored all the time. Neither with the bearings. You pop out the old ones, and install the new. (I have done one before, though) They get the main caps line bored *if* you are upgrading to new aftermarket caps. Sunnen has a quick and easy fixture for doing this, but it's about a $5,000 tool. We have an old Storm Vulcan oldschool "line bore anything" machine. I tell you, it is a beeotch and I'm the only one in the shop to run it, as nobody else wants to. And the few before me that have.... hated it. It takes about 5-8 hours to line bore just 3 caps on a small block chevy.... then it goes over to the line hone machine. I've done many V-8s in the past, and many huge diesel engines... but the worst to do is cam bearings as there's NO room to get your hands or even the steady rest in there, but I always find a way. It's so damn tight in there that I have to use a hose clamp on the super mini dial indicator to clamp to the bar, and a mini flex light with a telescoping mini mirror to indicate the housing bore and see in there... Those take about 12+hours to do, and I have NO margin for error. They have to be exact, straight and in line, and within .0005" (can't hone due to the babbit) and I use a home-made telescoping bore gauge to get these #s as you cannot fit a dial bore gauge in there. Ghetto... but with the right touch, I make it happen.

*IF* our big linebore setup could do a 2.2 head (bar diameter is too large...) it would seriously take me about 3+ hours to pull off. 3 x $70 = too much for someone to want to spend on a 2.2 head.

[RoadWarrior222]

Find a 1920s text on plant engineering and follow the procedure for rebuilding crank journals and making babbit bearing shells.

---------- Post added at 06:50 PM ---------- Previous post was at 06:48 PM ----------

Oh, just thinking, there's that knurling that's done to valve guides that perks them up for another 30K or so, could a similar thing be done?

[4 l-bodies]

This guy pretty sure has the equipment to alignhone OHC cylinder heads.
Torvinen Machine & Repair
35 12th St SE
Menahga, MN 56464
218-564-5385

[turbodaytona87]

*IF* our big linebore setup could do a 2.2 head (bar diameter is too large...) it would seriously take me about 3+ hours to pull off. 3 x $70 = too much for someone to want to spend on a 2.2 head.

Might still be worth it to me for a ported head, certainly not for a stock one.

[86Shelby]

Just for giggles while in school we attempted to repair cam journals on an OHC V6 head. It was a junk head so it was no loss if it didn't work. Shaved a little off the caps and a little off the towers. Then used a small attachment for the rod hone machine to hone the bores to size. It was akward, took 2 people using the hone and made a mess but it worked. It was not a perfect factory finish by any means. The finish was as good as you could get and the cam spun freely. We didn't run it on an engine as there were other flaws in the casting.

[crusty shadow]

a local shop by me has one of those cam saddle hones.
the equiment isnt expensive if you pick it up used off ebay.

[wallace]

My machinist does it. I watched him setting up a Porsche head to cut them for bearing because the journals were scored. I believe he got over $500 for the job and still thought he didn't get enough money. Looked like a gigantic pain in the ---, he was using the line bore machine he does blocks with.

[Juggy]

The larger diameter boring bar does not deflect like the one needed for our cam journals due to length. Also the smaller bar will most likely chatter. I think the cost would be prohibitive. I do have the bearings for this fix because I also have a nice ported head with cam bore damage. Here is an article laying out the prices for the specialized equipment.

http://www.enginebuildermag.com/Arti...g_subject.aspx

+1. also the smaller diameter stuf that could bore out the caps, are prolly going to be way too short to do them all in line, and most likely require 2 setups (which is a PITA because then you have to make sure everything you did from the first setup, will match up perfectly with the stuff on the 2nd setup)

[Directconnection]

The setup we have for ohc heads is really simple, but it uses dedicated fixtures for each style head.

You have 2 bronze bushings that is the same od as the id of the bores, and a bar about 3/4" or 7/8" Then, you have a collar that is tightened down by a setscrew to keep it on the bar, and carbide inserts that are soldered into that collar. The carbides are ground to give the perfect finished diameter when clamped to the bar. So, you play a game with the bushings on the 1st and last cam cap.... bore the middle ones.... then switch the bushing to the 2nd one and move the carbide collar over near the 1st and let it go through that w/out any end support (the bar is just barely rigid enough...) Then do the same switcheroo for the last cam cap. I think it's ghetto, but I've done it a few times for the Toyota 22re circle jerk races engines that come into the shop. Might be a collar for a 2.2 as it's an older setup...

[RoadWarrior222]

Eyeball and brake hone!