In a jam with a broken cam

[Tbay99Venture]

Even with the recent holiday progress has been slow. The cam rotated nicely, all lubed up. All the other bearings looked great too. I hand powered the oil pump and got everything primed and slipped the engine back into the vehicle Sunday afternoon. But it wasn't until tonight that I got the lower intake manifold on. This time I'm trying Victor Reinz gaskets. Last time it was a Fel-Pro set for the heads, and prior to that the LIM set I used came from the Chevy dealer.

But I won't have it running tonight. I didn't notice I had mixed up the bolts and put one a tad too short in for the belt tensioner. The starting threads got messed up in the head but I got that all repaired carefully with a 10mm x 1.50 tap & one of the shorter bolts that I could thread by hand to check progress. It looks like an 80mm long one will do the trick so things are on hold until tomorrow.

[Tbay99Venture]

It is running. Of course I am way behind on posting the bearing picts. And I managed to bust off the driver's side mirror when I rolled & hopped up from under the van after changing the fuel filter I have to wonder which team I am on.

[Tbay99Venture]

Here are the specifics, if you find you want to replace spun bearings.

Cleavite part number SH-1364S-80

In my area Godwin & Singer did the line boring. Sometime back in May a thread started on this site by somebody across the bay in Tampa with a different machine shop. So there are still options to deal with precision cam work. These guys have lots of cool things going on -- babbet work for some really old block was under way. Cast and then machined down with shims in place so they can be removed every some thousand miles to adjust for wear. And the next bay over was a big road tractor/trailer diesel head with overhead cams getting bearings.

[Tbay99Venture]

OK, time to summarize everything.

1) The nagging problem for this engine was a rumbling idle. After trying many different things, replacing a knock sensor and 1 O2 sensor there was not change. And I didn't think the sensors were bad so I was leaning towards removing and flushing the injectors.
2) The injectors weren't seeming to do anything more than make the idle annoying and the plugs weren't really fouled so I figured I'd keep up with the Frankenjecor thread and make my own cleaner -- can't mail them off due to the downtime.
3) The Vehicle nets almost 200K miles.

Now if you go back a few pages you will see the goo in the oil pan. We have another vehicle. Similar dally drive. VW, 2L with a bit over 200K miles. I took the pan off this weekend and... no goo. The oil change intervals for both machines was around 5K to 7K miles. Pinellas county is city but with a lot of 45MPH or so roads. I would not consider it severe and the Volks seems to agree. So I think the goo is because of too much fuel from a few injectors.

What that have to do with the cam?

Here are a few pictures of the break. Note that the middle bearings were the most worn in the block. My working theory is that as the miles accumulated some slop in the bearings allowed the oil to leak out and accelerate the wear. The cam is not solid so it will flex. Further, it is steal. As the machinest said when he looked at it, iron will trap oil a lot better than steal. So we have a self-machining situation. The cam becomes banana shaped. Stress concentrates near where the lobe is attached. Cracks begin to form and the cam rapidly begins to self destruct.

Notice in the pictures the cone shaped break in the metal.

All in all, the tubular steel cam is vulnerable to oil problems.

[3400-95-Modified]

The goo in your oil pan is from the lower intake gaskets leaking coolant into the oil and then the oils ability to lubricate a surface is GREATLY affected therefore destroying your cam bearings and snapping the cam.

It was that or you also had a bad head gasket which was contributing to the rough idle from coolant entering the cylinder.

[60dgrzbelow0]

OK, time to summarise everything.

1) The nagging problem for this engine was a rumbling idle. After trying many different things, replacing a knock sensor and 1 O2 sensor there was not change. And I didn't think the sensors were bad so I was leaning towards removing and flushing the injectors.
2) The injectors weren't seeming to do anything more than make the idle annoying and the plugs weren't really fouled so I figured I'd keep up with the FrankInjector thread and make my own cleaner -- can't mail them off due to the downtime.
3) The Vehicle nets almost 200K miles.

Now if you go back a few pages you will see the goo in the oil pan. We have another vehicle. Similar dally drive. VW, 2L with a bit over 200K miles. I took the pan off this weekend and... no goo. The oil change intervals for both machines was around 5K to 7K miles. Pinellas county is city but with a lot of 45MPH or so roads. I would not consider it severe and the Volks seems to agree. So I think the goo is because of too much fuel from a few injectors.

What that have to do with the cam?

Here are a few pictures of the break. Note that the middle bearings were the most worn in the block. My working theory is that as the miles accumulated some slop in the bearings allowed the oil to leak out and accelerate the wear. The cam is not solid so it will flex. Further, it is steal. As the machinist said when he looked at it, iron will trap oil a lot better than steal. So we have a self-machining situation. The cam becomes banana shaped. Stress concentrates near where the lobe is attached. Cracks begin to form and the cam rapidly begins to self destruct.

Notice in the pictures the cone shaped break in the metal.

All in all, the tubular steel cam is vulnerable to oil problems.

TeeBay...

If you like... you can PM me... and since we only live a few miles from each other, you are welcome to come by and use the latest version of "Frank" and the UMAX UltraSonic Cleaning Machine as well if it suits you like whenever it's convenient for you to do so. I'll give you a short walk through on its operation and with your permission, I'll videotape the results as a "Real World Test" to post back here and then you'll have a completely re-conditioned set of injectors ...for free. Just let me know what you think.

PS... I just found an extra set of "MR. INJECTOR" Filter Baskets & Viton "O"Rings w/removal screw tool that you can have to speed things up and improve the complete "newness" of your injector set. Alternatively, I can loan you the entire FrankInjector apparatus to take back home and use as long as you have a compressed air supply to pressurise the EFI Cleaning fluid cylinder. The important thing is to get that vehicle running in a reliable condition as soon as possible....and the less expensive the chores are to achieve that goal ...the better.

[Tbay99Venture]

Wow, I'm behind responding. Thanks for the offer (2nd time I think, but with the enhanced Frank now.) It sounds like a great plan, perhaps after the holidays? It's driving fine but I want to see what's happening with the injectors and I expect there's going to be substantial improvement by cleaning.