Author Topic: is my HEAD still good and functional??? (Read 5173 times)

goldarrow · « **on:** August 08, 2012, 06:46:52 PM »

1975 cb550 cylinder head cover. is my HEAD still good and functional??? need advise please. what can i do? or what should i not do? sand it down until it's smooth? leave it alone? thank you all.

after first round of soda blasting

then some more soda blasting

then even more soda blasting

and then even more soda blasting

i could probably do this all day long to get it cleaned up, BUT the surface area is pitted, all other chambers are nice and smooth

RAFster122s · « **Reply #1 on:** August 08, 2012, 07:00:40 PM »

The gasket sealing surface if pitted is what most people worry about. A machine shop can true and deck the head if it is fairly flat without much impact to valve clearance and compression. With radical cams and the like you would be fly cutting the piston tops for appropriate valve relief, etc. I would imagine the pitting in the combustion chambers would make it easier for carbon build up on the head. Yes your intake and exhaust ports/tracts are clean.
If you have the money MReich does very nice head work and porting and deshrouding the valves and other tricks would eliminate the pitting as the combustion chamber is reworked.
what's your goal for the rebuild?

madmtnmotors · « **Reply #2 on:** August 08, 2012, 07:45:13 PM »

Quote from: goldarrow on August 08, 2012, 06:46:52 PM

Is my HEAD still good and functional?

Obviously not. You've been inflicted with a serious malady

that manifests itself as an unhealthy obsession with 34+ year-old Honda motorcycles. Seek professional help...

or, just carry on!

goldarrow · « **Reply #3 on:** August 08, 2012, 08:06:19 PM »

Quote from: RAFster122S on August 08, 2012, 07:00:40 PM

The gasket sealing surface if pitted is what most people worry about. A machine shop can true and deck the head if it is fairly flat without much impact to valve clearance and compression. With radical cams and the like you would be fly cutting the piston tops for appropriate valve relief, etc. I would imagine the pitting in the combustion chambers would make it easier for carbon build up on the head. Yes your intake and exhaust ports/tracts are clean.
If you have the money MReich does very nice head work and porting and deshrouding the valves and other tricks would eliminate the pitting as the combustion chamber is reworked.
what's your goal for the rebuild?

did some googling around and found pretty much the same info - that the pitted combustion chambers would make easier for carbon build up in the head, and may also causes pinging. few more reading suggest to grind down with some small rotary tool like dremel....? to flatten the surface, at the same time not to change the shape of the chamber as this would impact compression numbers.

my goal to of the build is to keep it and hold on to it as long as i could so that i can pass it down to the kids if they want it. but well, budget is really tight, or actually no budget at all, trying to spend only what's really needed at hand. yes, have read many posts about MReich's work. one of many capable and talented men on the forum, but i just can't do his service at the moment. perhaps later down the road when i can actually afford to do this properly.

Quote from: madmtnmotors on August 08, 2012, 07:45:13 PM

Quote from: goldarrow on August 08, 2012, 06:46:52 PM
Is my HEAD still good and functional?

Obviously not. You've been inflicted with a serious malady that manifests itself as an unhealthy obsession with 34+ year-old Honda motorcycles. Seek professional help...

or, just carry on!

yes, i have been inflicted with bad decease of vintage honda virus, and it just keeps manifesting in me and nothing will cure this. hence this is why i'm here seeking professional help from this site

Retro Rocket · « **Reply #4 on:** August 08, 2012, 08:44:19 PM »

Quote

is my HEAD still good and functional???

Yes, but your eye's are too close together and your ears look funny....

goldarrow · « **Reply #5 on:** August 08, 2012, 08:53:05 PM »

Quote from: Retro Rocket on August 08, 2012, 08:44:19 PM

Quote
is my HEAD still good and functional???

Yes, but your eye's are too close together and your ears look funny....

And that's all of us lol

crazypj · « **Reply #6 on:** August 08, 2012, 09:01:53 PM »

DON'T use a Dremel.
It's way too aggressive with sanding rolls.
I would get some 180~240 grit wetordry and 'polish' it by hand (probably by thumb

)
Unless your racing, don't worry about it too much, knock off any sharp edges to the pits and put it back together.
If a head turns up at right price in future you can always swap it out (or have your haed skimmed and chambers re-profiled to a 'better' shape

)

cgswss · « **Reply #7 on:** August 08, 2012, 09:23:11 PM »

From what I see, I think you have set your self up for two things. One simple, one not so.

First as already mentioned, take the bare head to a machine shop and have it surfaced. Talk to the local M/C shops and see who they use. Any shop and do it, but a shop that doese a lot of bike work will have a lot less set up time an time is money.

The second part is that now you will need a valve job. If I were doing it, I would have a 3 angle valve job done. The problem is that you should do the whole thing. That means guides and seals. On jap bikes, guides are oversize and have to be reamed to the correct size. Not that hard, but you have to have the tools. In addition, most will say on this bike you don't grind the valves, You have new seats cut, and most will replace the valves. Again, this is all stuff you can do yourself, but the tools can get real costly. If I were in your spot I would contact someone like Honda Man and show him what you have, explain where you want to be, and see if he will do the work for you. THis part is NOT going to be cheap. And it will take some time to get one.

I would not worry about the chambers (other then the valves). Your not going to be racing the bike, I very much doubt it will be any sort of problem for you.

bryanj · « **Reply #8 on:** August 09, 2012, 12:47:54 AM »

Combustion chambers---seen way worse run no problem

Gasket surface---good clean and use it will be OK 99.99% of the time

Your head---no idea, what does your trick cyclist say

crazypj · « **Reply #9 on:** August 09, 2012, 06:36:05 AM »

You really DON'T need to go crazy with head reconditioning.
Don't worry about valve guides if there is less than 70~80,000 miles on motor, unless you can see rust spots they are probably fine.
It is not a trivial job to change guides
SODA blasting won't damage anything but I would still check guides for wear, fit new valve stem seals and new valves to at least the cylinder where the corrosion is - if there is any pitting on a valve stem, change valve (post pics, they may be fine)
Hit the valves with a wire wheel, the valve is harder than the wire (or should be)
Get a 3 angle valve seat cut, Serdi or Neway, grinding takes way longer
as bryanj said, we only know about chunks of metal, you'll probably end up paranoid depressive with all the 'information'

goldarrow · « **Reply #10 on:** August 09, 2012, 08:35:50 AM »

Thanks guys for all these wealth of info. And yes I was pretty much paranoid over the pitted chamber.

No idea what 3 angles valve job is, even with much reading. Need picture of for comparison. But it doesn't sound like it would benefit me much as I won't be racing on this bike, let alone riding it in general.

Looks like wet sanding with my thumb is on the To Do list and will take closer look again in the valve guide holes for excessive wear.

Hear are some pics of the valves when took apart few months back.

Have not cleaned or polished them yet.

More valve pics

Mostly just carbon deposits and build up?

Let me know if more pics needed.

My head...too many things going on in there right now....

Duanob · « **Reply #11 on:** August 09, 2012, 12:56:12 PM »

How married to you on doing it yourself? Personally I would hand it off to a good machine shop and tell them I want to first eat off it and then install it when I get it back.

goldarrow · « **Reply #12 on:** August 09, 2012, 06:38:00 PM »

Duanob, i kind of still want to eat off plate at dinner table, until i can afford to eat off machine. as it is i'm already eating ramen almost every other night after work. being able to eat off machine means much more money will go to machine shops and no food on table. and yes, i'm pretty much married to this bike, she's my second.

so, i chose the cheapest route for now by sanding and polishing with wet/dry sandpaper. and here's how it looks after about an hour or so. smoother but still pitted with carbon on it. should i polish some more? or call it done and move on?

here are some pics of camshaft bearing surfaces

more camshaft bearing surfaces

and one more camshaft bearing surfaces

are thse too worn? normal wear? leave it alone and move on?

thanks

RAFster122s · « **Reply #13 on:** August 09, 2012, 10:52:32 PM »

Polish them up with some 1000wet dry used with plenty of water. But, when you run your nail across the width of the bearing surface do you feel any bumps or grooves? They look prettygood I think, Ive seen worse that were useable.

bryanj · « **Reply #14 on:** August 09, 2012, 11:06:43 PM »

Leave the bearing surfaces alone they are normal

Leave the combustion chambers alone they are good enough

Claen the gasket surface better

goldarrow · « **Reply #15 on:** August 10, 2012, 04:07:39 PM »

I feel like my head is spinning now problems after problems

To the left is my valves cover, right is what got off feebay couple of months back for $30, I needed to replace some tappet covers that were boogered up.

Well, at least 2 of my rocker arms look badly pitted, can these be straight swap and look for the best condition and swap them out?

dave500 · « **Reply #16 on:** August 10, 2012, 04:29:04 PM »

idealy the rockers mate as they wear together with the cam lobes,so long as none of your lobes look worn unevenly itll be ok to mix and match the best ones,have you seen how to use a long 6mm bolt to pull the shafts out releasing the rockers?you also need to use the best cover with the least slack in this area where the shafts rotate,i stole this photo.

just chamfer those oil feed holes like this.

carefully run a draw file over the covers gasket surface and nick off any tiny high spots,same on the heads upper mating surface.

goldarrow · « **Reply #17 on:** August 11, 2012, 10:09:22 AM »

Sorry this may be stupid question but I just don't want to mess it up. What do I use to chamfer the oil feed holes? Tapered bits on drill? Thanks

crazypj · « **Reply #18 on:** August 11, 2012, 10:47:05 AM »

I use one of these ( a lot)
http://www.harborfreight.com/3-in-1-hex-bit-countersink-tool-68535.html

Valve stems need to be clean to check, carbon build up doesn't mean a thing and is normal

madmtnmotors · « **Reply #19 on:** August 11, 2012, 06:05:22 PM »

Quote from: crazypj on August 11, 2012, 10:47:05 AM

I use one of these ( a lot)
http://www.harborfreight.com/3-in-1-hex-bit-countersink-tool-68535.html

Valve stems need to be clean to check, carbon build up doesn't mean a thing and is normal

+1. The countersinks are the tool. They do not "Pull" themselves into the material. Drill bits tend to grab and pull themselves into the material (since that's what they are designed to do) often cutting too deep when used to attempt a simple champher (or countersink).

bryanj · « **Reply #20 on:** August 11, 2012, 11:55:42 PM »

The one on the left looks like the cam has been starved of oil and worn the rockers away, what does the cam, especialy the lobes, look like.

Whilst idealy the rockers should stay with the cam lobes they have run on, when they are still in good order AND THE CAM LOBES ARE OK it is OK to swop them out

goldarrow · « **Reply #21 on:** August 12, 2012, 04:13:38 AM »

Some of the cam lobes are pitted. I got a much better condition 650 cam as a replacement. I ended up swapping out 3 rocker arms, and many adjuster screws. I think the valve cover is set and ready. Will put up pics later.

bryanj · « **Reply #22 on:** August 12, 2012, 05:13:31 AM »

With the state of the rockers I suggest you make sure that the oil restrictor jets in the dowels at the base gasket are clear of any and all debris(especialy silicone bits)

goldarrow · « **Reply #23 on:** August 12, 2012, 03:37:58 PM »

Here's pic of valve cover

Will make sure that the oil jet is clean before installing the cylinder

goldarrow · « **Reply #24 on:** August 13, 2012, 08:46:01 AM »

Sorry this may seems like repost from my project build thread, just want to make sure I don't mess things up badly

So, Over the weekend, got some time to assembling few pieces on the motor...

Checked to make sure the two oil jets/nozzle are not clogged up, blown off with compressor and clean with wd40

Also chamfer the two oil holes as instructed

Installed base cylinder rings, laid the gasket down, face up....the edge of the gasket sticks out of the barrel when installed, should I trim it down?

This picture the gasket seems to sticking out a lot because the barrel is not full seated to the base case as I was just finished putting back on the cam tensioner

Another problem is the top gasket, oil hole on the gasket is off the hole, should I also trim this down?
Left oil hole

Right oil hole

The gasket holes for cylinder bores are all good

crazypj · « **Reply #25 on:** August 13, 2012, 09:40:15 AM »

I would use a scalpel and trim hole so 'O' ring is centered.
The ring will distort and you'll get an oil leak within a few hundred miles (it will still weep after a few thousand, they all do unless you dowel the hole so 'O' ring is supported, see ffJMoore 550 build)

RAFster122s · « **Reply #26 on:** August 13, 2012, 10:42:21 AM »

You need to use some chemicals & remove all traces or the old gasket or you are asking for trouble. Correct side up on headgasket? If so, yes trim the holes so the orings are centered.

goldarrow · « **Reply #27 on:** August 13, 2012, 10:50:45 AM »

Thanks crazypj and rafster. I'm mocking up the assembly right now and havent tighten anything yet. Just want to get an idea of what and how things go back on

Also another question, the two oil dowels/nozzles. Which end is up or down? One end is round that looks like it will go into bottom case, and that's what I did. just want to make sure. But a pic that was in ffjmoore engine build threat shows to the contrary.

I stole this pic from ffjmoore, oil dowel round ends looks like it's on pointed up.

dave500 · « **Reply #28 on:** August 13, 2012, 12:49:55 PM »

your oil dowel/restrictor is the correct way up,make sure its clean underneath,youll see how its design invites the trapping of material blow it out and make sure you can see through the pin hole.

goldarrow · « **Reply #29 on:** August 13, 2012, 03:05:08 PM »

Quote from: RAFster122S on August 13, 2012, 10:42:21 AM

You need to use some chemicals & remove all traces or the old gasket or you are asking for trouble. Correct side up on headgasket? If so, yes trim the holes so the orings are centered.

Cleaned up some more old gaskets, filed down the holes so o-rings fit better now. But which way gasket is face up? The way I have in pics are good?

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Author Topic: is my HEAD still good and functional??? (Read 5173 times)