Slant Six Forum
https://slantsix.org/forum/

Drilling rear cam bearing
https://slantsix.org/forum/viewtopic.php?t=53194
Page 3 of 3

Author:  walpolla [ Sun Sep 01, 2013 5:18 am ]
Post subject: 

Quote:
.......... Hope it works. Go for it, since you aren't going to listen. You aren't doing this right. Copy that, and then do whatever your going to do. I'm all for you proving us wrong. ............CJ
Co-incidentally this little gem came up on one of my local forums a little while ago. Classic !
Actually I think even duval67 will get a chuckle out of this one. Please don't be offended, it is all in jest.

click here

regards,Rod :lol:

Author:  duval67 [ Sun Sep 01, 2013 5:56 am ]
Post subject: 

I did install new bearings, just didn't measure beforehand. Honestly did not know that that was something that needed to be done before I did it. Either way, engine building and measuring aside, if something is firmly pressed in, it's not going to move, and if whatever goes between the press fit items does not bind on them, there is no reason for anything to move.

Author:  CNC-Dude [ Sun Sep 01, 2013 11:29 am ]
Post subject: 

That would be a fair assumption to make, but something made it spin in the first place and im sure it was pressed firmly in place then. You only fixed the results of it spinning, but you didn't fix the cause of it by simply replacing it. Spinning a cam bearing is really pretty rare in any engine, unlike a spun rod or main bearing, and when it occurs, it usually hints of a deeper problem.

Author:  Rick Covalt [ Sun Sep 01, 2013 2:11 pm ]
Post subject: 

I know that when you install new cam bearings sometimes the ID of the bearing is too small. Which I am guessing is because the machining of the block at the factory was to small. This happened to us when we built the motor in Ryan's Dart. The cam would not slide into the bearings the whole way. It had to be taken back to the engine builder and he had to shave the ID of the bearings to get them right.

This has happened to others on the sight as well. I'm pretty sure it was Doc that told me the factory had several sizes of bearings for each location to get the right tolerances that they needed.

Is it possible that your cam went all the way into the engine but the rear bearing just did not have enough clearance and it seized on the cam and spun?

Just thinking out loud!

Rick

Author:  SlantSteve [ Sun Sep 01, 2013 2:54 pm ]
Post subject: 

Quote:
Either way, engine building and measuring aside, if something is firmly pressed in, it's not going to move, and if whatever goes between the press fit items does not bind on them, there is no reason for anything to move.
That's a good theory but it doesn't apply in your case,your old bearing moved and your new bearing moved as well.
I understand your frustrated,you DID listen patiently to others,
i refer to the other thread...you cleaned out the gallerys and refitted the head to no avail,now your getting frustrated and more importantly pressured for a car. Put that together with the " enthusiasm of inexperience" and you start to cut corners. But hey,good luck with the short term fix,but I think you would do yourself a favour if you bought a good running engine to replace this thing and take the pressure off you for transport,to me it sounds like it was pretty suspect from day one and will be a can of worms if you get into it.If I read it right you will then have 2 engines to play with at your leisure and do a good rebuild using the best of both.good luck with your fix!

Author:  duval67 [ Sun Sep 01, 2013 3:34 pm ]
Post subject: 

The engine seems to be oiling just fine now and has been run for a couple hours today with no problems.
Buuuut the engine has very little power and can't even get over 80 km/h unless it has a hill helping it. It doesn't bog down and it accelerates smoothly, just very very slowly.

Author:  SlantSteve [ Sun Sep 01, 2013 3:50 pm ]
Post subject: 

Good to hear it got you out of trouble,but I wouldn't trust it for too long.the lack of power is the least of your worries, I wouldn't waste too much time on this engine, it's had no oil to the top end for who knows how long, it's had a spun cam bearing and it was soaked in diesel when you got it? Why did they do that? All in all it's had a tough time! But it's great you coaxed a little more out of it! There was a quirky comedy show on tv here in Australia called " bush mechanics" it's about all the bizarre things people do to keep their junk running without parts and when they are in the middle of nowhere... I think you could teach them a thing or two!

Author:  Reed [ Sun Sep 01, 2013 4:29 pm ]
Post subject: 

Quote:
The engine seems to be oiling just fine now and has been run for a couple hours today with no problems.
Hooray. I will keep hoping for you that the cam bearing holds out. In the mean time, you really should purchase another motor and rebuild it while the one in your truck lives on borrowed time.
Quote:
Buuuut the engine has very little power and can't even get over 80 km/h unless it has a hill helping it. It doesn't bog down and it accelerates smoothly, just very very slowly.
You swapped in a mechanical camshaft and lifters, right? What cam profile? Stock? What year stock? Pre-72? Did you adjust the valve lash correctly? Did you degree the cam? Is your vacuum and mechanical timing advance mechanisms working correctly? Did you set your base timing correctly? If you have an automatic transmission is the kickdown hooked up and adjusted properly?

Author:  duval67 [ Sun Sep 01, 2013 4:36 pm ]
Post subject: 

Thanks guys. Bush mechanics sounds hilarious--I'll have to see if I can find it online. Plan is to get the truck to Guelph from Ottawa (500km ish) with a buddy following me. Then I'll pick up an engine from Ryan and slowly build it to replace this piece if junk.
I ended up using the hydraulic valve train actually, all components of it. Standard trans. In terms of degreeing the cam--all stock from this engine went back in so I just lined up the marks on the two sprockets. I assume that's what it is as stock, right?

Author:  Reed [ Sun Sep 01, 2013 5:14 pm ]
Post subject: 

Bush mechanics. Sounds like "the "bush pilots" that work in Alaska where I grew up. They have to do the same kind of thing- keep their planes running in the middle of nowhere with only what they bring with them.

It is very easy to get one of the timing gears a tooth off. If you are sure you lined the timing gears up correctly, then I would start checking things like the accuracy of the timing mark on the vibration dampener, your base timing setting, and the timing advance mechanisms in the distributor.

Author:  duval67 [ Sun Sep 01, 2013 6:23 pm ]
Post subject: 

It was a dumb thing--all my testing was without the hood. Way too much drag for the truck to get out of its own way. All is good now, aside from my battery dying when I went for a drive. Either VR or alternator. I have replacements of both.

Page 3 of 3 All times are UTC-07:00
Powered by phpBB® Forum Software © phpBB Limited
https://www.phpbb.com/