The Bad Idea - VF750F Interceptor restoration

[620dark]

All kinds of goodies showed up yesterday:

I like the date code on the back - new old stock apparently!

New to me head and tensioner!

Fuel level sender - given the number of times I've walked to get gas, I consider this vital ;D

Scrub scrub scrub..

After I finished scraping the old gasket stuff off the head, I used a brass Dremmel brush to clean it up, and then washed the head in dish soap and hot water. After drying it, I sprayed it down with WD40 to prevent flash rusting. Next steps are to remove the valve springs, check their length, and replace the valve stem seals. I should probably do the rear head as well, which means I should probably remove the rear head. Which means I should probably pull the motor out of the frame. Or maybe that can wait till I know it runs ;D

 

[620dark]

Well, two steps forward, one step back. I replaced the valve seals on the new front head, and that went very well:

Note that the valve springs are progressive, and the tight coils go on the bottom. Also note that there are two spring washers, one for each spring:

This is the tool that makes this job easy:

This little device takes the valve keepers off with one whack of a hammer, and then reinstalls them with another. It took me less than 30 minutes to do all eight seals. Worth every penny paid!

However, when I pulled off the old cylinder head, I found that the front chain guide was broke at its mount to the block. Well shit. I found one on Ebay local to me, so I pulled the trigger on it. Sadly, the head can't go back on until the new guide is installed.

Now the question is, do I pull the motor out so I can replace the head gasket on the other head? I can do the valve stem seals in place, but the motor's gotta come out to pull the head. Decisions decisions...

 

[Cafe-XV750]

Ya got it this far and have time waiting for the other part - I say pull it and replace. Peace of mind while you're riding. Of course you might find other 'discoveries' ???

 

[620dark]

Yea, you're probably right. I'll probably slap the oil pan back on it and pull the motor so I can put it on the bench. Then I gotta paint the frame though! You monsters, what path have you sent me down? ;D

Also, the service manual says to use sealant on the rubber valve cover gaskets. I didn't see any sealant on the old ones, and there was no indication of leaking. I thought the point of the rubber was not to have to use any sealant...what is the advice of the learned readers of this thread?

 

[Hoosier Daddy]

If it has a ridge in the valve cover for the rubber gasket like most, I use a little bit of Permatex High-Tack on the valve cover only. Just enough to hold the rubber in place for easy installation.

 

[620dark]

And I can huff the high tack for fun too right? ;D

That sounds like a plan - the valve covers do indeed have an indent in them, and the gaskets are an upside down "T" shape. Thanks!

 

[620dark]

Ok, the front cam chain guide arrived yesterday, so I got to work installing it and test fitting the head:

Well there's yer problem!

Question for you fine folks - is the guide supposed to stick up like this?

Even with the head temporarily installed, it's springing the chain towards the center of the head, which kind of seems like what it is supposed to do, but I'm not sure...

That's about as far as I got, as getting the cams and gears installed was trying my patience. The factory service manual is a little vague about what position the cams should be in when the timing pointer is aimed at the "2-4" mark. I think that they need to be aimed about 45 degrees counter clockwise from straight up and down. That makes sense from a not wanting any of the valves to be under load sense, but the manual isn't very clear.

Does anyone have a good walkthrough of the cam replacement / reinstall procedure? I couldn't find much info with Google...

 

[620dark]

This video has a pretty good walkthrough of installing the cams on a Magna:

http://youtu.be/CQv_r8Vuevs

I think this answered my questions about installing the cams. We'll see this evening I guess!

 

[620dark]

After fighting with the cams for a while last night, this happened:

Guess I gotta clean up the frame now too...

 

[620dark]

Alright, I got the motor up on a table (and discovered a missing nut in my hoist along the way ), and really dug into it.

Despite my best attempts, I cannot get both cams into place. The cam chain appears to be too short, which doesn't make much sense as it fit on the cams before I removed it. Does anyone have any thoughts or suggestions about this? I've even tried removing the tensioner to give myself more room and slack to install the cams, but no luck.

Has anyone done this job before? Help!

 

[bikeboy]

The chain may be caught up on the crankshaft sprocket? Does it rotate with the crank smoothly?

cheers
ian

 

[620dark]

Yea, the chain was a little loose at the crank, so I freed it up. CrazyPJ gave me some advice on how to muscle the cams and sprockets into place, and I was able to get them on. I'm a bit concerned about how tight the cam chain is compared to the other bank, so I'm going to pull the oil pan off again to check to make sure the chain is not still bound up.

 

[620dark]

Does this front lower chain guide look like it is in the wrong place? The chain feels too tight, and I'm worried this is the issue:

 

[620dark]

Found the issue, loose nut behind the wrench I purchased a chain guide for a Sabre/Magna, not an Interceptor, and they have almost 1" of height difference in the mount.

I just purchased the proper parts on Ebay, so hopefully that will put this motor saga to bed. Sheesh.

 

[620dark]

Today is like Christmas - 750 and CB360 parts arrived today!

Hopefully I can get this darn motor back together soon now!

 

[620dark]

Also, the new radiator cap arrived to go with the thermostat and fan switch:

 

[620dark]

Yup, the cam chain guide was the fix. I had the head and cams in place and timed 10 minutes after I installed the proper guide. The motor spins over soooo smoothly now too.

I have to set the valve clearances, reinstall the various covers with their new gaskets, and replace the o rings on the coolant pipes. New spark plugs and boots are on their way, and that should wrap up the engine work. I hope, heh.

The weather should improve the end of this week, so I'll strip the frame down further and get it cleaned up and ready for some rattle can silver. Then it will be time to see if all this work pays off!

 

[interceptor]

Good job! Still waiting for some warmer weather on the east side, too. I think I am going to get the 360 out of storage and ride it home today. But there is a chance of rain tonight, and riding in 30's with rain in the morning doesn't sound fun to me.

 

[Cafe-XV750]

My ZX900 ready to go! Woke her up this past Sun. Hope to see these Interceptors soon ... perhaps Depot Town Tues bike nights.

 

[620dark]

I think there's a better chance of seeing the 360 in Yipsi anytime soon ;D I have to swap the intake boots/manifolds on it, and hopefully that will cure the hot running woes.