Heads and Valves and Rust and Pits

[hubeerjw]

I took my heads to get cleaned at my father-in-law's shop and we removed the valves and springs, and my front head has some pits in it (along with a few valves.) It isn't too bad, but I wanted to see what everyone else thought. Should I try to find new heads, or do I just use these? They will be going on my trubo drag bike and the motor may not last long anyway, so I am leaning on just using these. Here are some pics... let me know what you think.

 

[one2dmax]

It's hard to tell how much of that is pits vs casting stuff. I'd lap in the valves and call it a day.

Sean

 

[4gasem]

I'm with Sean on the heads. Can you have the valves and seats ground? Triple grind?

 

[KJShover]

+3, looks alot like casting marks to me as well. 90% of that would polish right out if your so inclined. But like Sean said, just lap in the valves and call it a day.

 

[naughtyG]

just lap in the valves

Sorry to be so green, but what does that mean - lapping the valves? :ummm:

 

[KJShover]

Sorry to be so green, but what does that mean - lapping the valves? :ummm:

It's basically "facing" the valve to the head. Lapping compound is just a mild abrasive that is applied to either the valve or the seat, depends on who does it, personally I put alittle on both.

The valve is then rotated either mechanically or manually to achieve a better valve seal.

Here is a good page that describes a valve job.

http://www.dansmc.com/valve.htm

 

[naughtyG]

so 'lapping' is just another word for 'grinding', right?

 

[KJShover]

Kinda, its more of a cross between grinding and polishing.

 

[lankeeyankee]

Doesnt look like the pitting is where the valves will seat.
I would check the chamber, valve guides and valves spec with the service manual if all is in spec than I would
Throw the heads in the dishwasher HOT Cycle (Yes the dishwasher is awesome for this, just dont get caught by your wife)
Put new valve seals in, lap in the valves and work on the exhaust ports of the head.
Finish em off with a few coats of VHT paint.

 

[hubeerjw]

Well, I lapped the valves, cleaned them up, and assembeled everything. I now have 2 heads ready to assemble. The front left cylinder (#1 I believe) is the worst, but it cleaned up pretty well. I'm not expecting this motor to last a super long time anyway so it should work for what I need it to do. Getting the keepers back in and compressing the springs can be a little tricky. I made a tool out of a 3/4" copper 'T' with about a 8" piece of 3/4" PVC pipe inside it. I cut a small piece out of the bottom so I could stick my chubby little finger in there and hold the keepers. I can post pictures if anyone is interested.

Thanks for all the help and comments!

Jeff

 

[lankeeyankee]

Well, I lapped the valves, cleaned them up, and assembeled everything. I now have 2 heads ready to assemble. The front left cylinder (#1 I believe) is the worst, but it cleaned up pretty well. I'm not expecting this motor to last a super long time anyway so it should work for what I need it to do. Getting the keepers back in and compressing the springs can be a little tricky. I made a tool out of a 3/4" copper 'T' with about a 8" piece of 3/4" PVC pipe inside it. I cut a small piece out of the bottom so I could stick my chubby little finger in there and hold the keepers. I can post pictures if anyone is interested.

Thanks for all the help and comments!

Jeff

Wanna know a trick for putting the keepers on??

Long skinny screw driver with bearing grease the keeper stays on the tip of the screw driver with the grease to place it on the valve stem.. to late now.. Ol mechanics trick
I am sure you will be doing it again.

 

[hubeerjw]

Thanks for the tip lankee... have you tried removing the valves on the VMax yet? There isn't a good tool that I know of to compress the springs and it is almost a 2 man job... I was able to get a few of them in myself, but we ended up getting 1 keeper in each valve, then my pretty large brother-in-law would use my home made tool and push down on the springs and I would try to work the other one in place with my finger. We also used a 6" 'C' clamp on a few of them and that didn't work too badly either.

 

[lankeeyankee]

Yes Jeff I have done valve jobs on VMAX heads. Its a bitch until you find the correct combination. Here is what I did to make the job of removing and installing VMAX valves easy.

1) Goto your auto parts store most rent tools for free. (advance / autozone)

2) Take a spark plug socket and shave 2 notches out of the side the whole length of the socket wall. about 1/2 in both sides... )Dont use a piece of PVC pipe its not strong enough)

3) Use the spring compressor on the head using the edge of a work bench.

Here is the biggest tip. Long skinny screwdriver with axle bearing grease on the tip.

4) Compress your valve spring and knock the keepers off with a screw driver.

Installing new valves.

Just compress the valve spring all the way, apply the grease to the tip and postion the keeper on the tip of the screw driver and direct it onto the stem of the valve
Also if you put grease on the stem of the valve its an added bonuse for holding the keeper on till you decompress your spring..

Piece of cake , and your not crawling around on the floor looking for keepers