CB500T Head gasket replacement

Awesome that did the trick. It seems the stem seals are pretty stuck on. Any tips for getting them off?
 
If you're talking about this, after the 6mm bolt and the retainer plate is removed it should just pop off, it doesn't really lock into anything but it's probably stuck from being there for years. Just don't try to remove it from the center as you'll be reaching into the valve guide, hook it from the outside edge with a pick or something like a cotter pin puller.
 
Finally got the valve stem seals off and the valves clean, just to discover the seals in my kit are a completely different part! Guess I'll have to order some more. Unfortunately 4into1 is out of stock so I suppose I'll have to get them off those guys in Houston collective. That will set me back a little while so I'll keep you posted after I finish cleaning the rest of the engine.IMG_20201018_141254.jpgIMG_20201018_141247.jpg
 
Would you recommend those over the those guys in Houston ones?

https://www.those guys in Houston.c...vh2tzLnKhwcRb-XTqWwdsHLCXoUbioRoCI6UQAvD_BwE#

They just ship quicker and I want to get the bike back together in the next week or two.
 
The those guys in Houston ones are $16 EACH

"Your Price: $16.00

In Stock




those guys in Houston Part Number:4089


  • Replaces OEM Part:14791-319-005
  • Qty:Sold Individually"
That's a huge difference in price over the ones on ebay.

"Honda CB500 CB500T Valve Seals Cap set x4pcs 1975 1976 14791-319-005"


But it's your wallet :)


 
Yeah I definitely saw that, but lower in the page it says sold in packs of four so I have no idea. I sent them a message and asked which one it was so I guess we'll see. $16 a piece is absurd so I really hope it's a pack of 4.
 
So I finally got a closer look at the piston rings and it seems that both edges are beveled, and to the best I can tell are identical. Does this mean it just doesn't matter which way I put them in, or should I be worried about this set?
 
Better, more close-up pictures will help someone like LDR (who has undoubtedly installed hundreds of thousands of rings in his life) identify something about them that most of us can't see in a general picture
 
Sorry for the hold up! Haven't had a chance to focus on the bike for a little while. I did my best to gather some better photos of the rings. It's a little difficult to get a good close up on the ends but tried!

Here are the ends, to me it looks (and feels) as though both of the outside edges are beveled. Perhaps you guys will notice something I missed. There's one photo of the iron ring and two of the chrome (this is just one set).
dark close up.jpgshiny close up.jpgshiny close up 2.jpg


Here you can see both sides of the rings. There's no indicator markings and they look the same to me.
side 1.jpgside 2.jpg

Thanks for all the help! Let me know if the photos don't show up. We can try something else if it's not working.
 
Yeah weird. Is it a bevel on the inside edge or outside edge that I'm looking for? It definitely seems like both outside edges are beveled and kinda seems like one of the inside edges has a sharper corner than the other, but it honestly might just be in my head. Maybe this is designed to be usable either way?
 
If there is a bevel the wide section is top but I don't see any bevel. Looked at the 350 FSM and the ring picture they show looks like your rings. As long as the end gap and side clearances are good just install them and proceed.
 
Alright, sounds good! Thanks! Do you guys have any recommendations for a good timing light? I'd rather not spend $100 bucks on one if I can help it but I'm not sure what sort of thing I need.
 
You can just set the static timing (test light) to get started, but at some point you should get a strobe to make sure the advancer is working properly and your timing is reaching the full advance marks.
 
Getting a lot of the engine back together today! Do y'all recommend using any gasket sealer on the rubber seals for the oil galley on the head gasket surface?
 
NO!....Not unless you are comfortable with any excess sealant being perfectly positioned to restrict or plug the oil feed...... I'm not!
 
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Haha thanks! That was my instinct. Hopefully gonna have the engine back together tomorrow! I can't wait. Thank you for all the help!
 
I'll have to tune the carbs soon, do you guys have some advice on how to do this? Should I purchase a set of vacuum gauges?
 
We wish you well. It's my favorite Honda engine, and though it has some unusual aspects of working on it, the unique aspect of it has always been of interest to me. Be careful about the cam timing, and be sure to get the exhaust cam position set before you slip the chain through the head to the intake side where you'll put in the master link. If you run into anything you need advice for, or any difficulty in dealing with the cam timing marks, be sure to ask before moving forward.
 
lassmanjm said:
I'll have to tune the carbs soon, do you guys have some advice on how to do this? Should I purchase a set of vacuum gauges?
Click to expand...

It's just a twin, I set carbs on a twin by ear. Since you have the ports for connecting gauges to (IIRC the 500T has them), you could do it that way.
 
since the CB500T carbs have vacuum ports already you should definitely use them.
Vacuum syncing the carbs made a huge difference on mine. It's like a different bike after they're synced.
 
Awesome thanks! I'm having a little trouble with the head gasket and oil galley o rings. I put the 3 dowels in first, then the two o rings on. The head gasket has two holes that are clearly bigger (indicating the proper orientation), but I can't fit those over the o-rings by hand. Should I cut it out a little, or just put the head on and assume the compression from the bolts will do the trick?
 
lassmanjm said:
Awesome thanks! I'm having a little trouble with the head gasket and oil galley o rings. I put the 3 dowels in first, then the two o rings on. The head gasket has two holes that are clearly bigger (indicating the proper orientation), but I can't fit those over the o-rings by hand. Should I cut it out a little, or just put the head on and assume the compression from the bolts will do the trick?
Click to expand...

You can safely (and absolutely should) open up the holes of the gasket very carefully to accommodate the diameter of the flat o-rings properly. The last thing you need is to fire it up and have oil leaking around the o-ring at the head gasket, it might be fine for a while but eventually will cause a significant leak and possible oil flow issues on an engine that can't afford ANY of that. I used a dremel to open up mine, since there's metal in between the layers of gasket material.
 
^^^In fact - and I've bought at least 5 top end sets in the last 2 years, and 3 different brands - they're all that way now best I can tell.
 
Yeah the dremel was a great idea. Definitely did the trick! I've got the engine all together and the cam chain hooked up. Would you take a look a the timing marks and the master link (sorry the one photo is blurry, but you should be able to make out the marks)? Just want to make sure the timing looks good, and that I've riveted the master link enough. I'm not quite sure how much to compress it and I don't want to over/under do it. Thanks guys! We're in the home stretch!


PXL_20201106_232253580.jpgPXL_20201106_232258903.jpgPXL_20201106_232310117.jpg

PXL_20201106_232418463.jpgPXL_20201106_232359318.jpgPXL_20201106_232350587.jpg
 
The timing marks look good, you can't ever get them any closer than that. The master link looks good too, but the way I test to see if it's staked enough is to take a flat screwdriver and gently pry it in the direction you'd remove it, then see if the side plate moves at all when you push it "back on" so to speak. If there's still any movement of the side plate after staking it, you need to give it just a little more... but not so much the end of the pin mushrooms and cracks, because the little pieces could fall off later. You want the side plate staked against the shoulder of the pins tightly. Now that you've done it once, you can see all the precautions I tried to point out in the beginning.
 
Great! Thanks. I figured as much about the timing but was just a little concerned since it didn't perfectly line up. I'm hoping to get it back on the frame tomorrow and I'll keep y'all posted!
 
BTW, have you rotated the engine a few times and re-checked the marks? Gently the first time around just in case. Now is the time to adjust the cam chain and valves too, since you have nothing in the way.
 
Yeah I have! Definitely got to do the valve clearances, but that reminds me; is there a specific place in the cycle to engage the cam chain tensioner? The manual just says to do it but not in a specific place.
 
I always do it with the valve covers off so I can watch the exhaust side get tight during the opening of a valve and then hold it in that position while releasing the lock bolt on the tensioner so it can tension the intake side of the chain. Tighten the lock bolt before you move the engine again.
 
Hey quick question, the manual says use valve clearances of .03 mm, but that seems so tight. My tappet gauge set doesn't come close and my feeler gauge only goes down to .038 mm. I know not to really trust those guys in Houston but the say use .08 mm. Have you gone with the .03 in the past? The gauge is so flimsy I can barely get it in the gap.
 
Just another thing they aren't correct about. The factory setting is "tight" in size but it is what the factory intended and the valvetrain was designed for, however a feeler gauge of that size is harder to find so we generally set them at .05mm (.002"). Remember the adjustment is made between the follower and the cam lobe (not the follower and the valve stem)
 
.038 mm is .0015".......That will be fine IF you can set them there, although I would recommend you set at .050 mm /.002"............
 
Awesome, got them set to ~.05 mm. Could you take a look at the cam follower adjusters though? You said have the tick marks facing away from the head, like so?

PXL_20201109_193545611.jpg PXL_20201109_193557972.jpg

The tick marks are kinda hard to see and are definitely not perpendicular to the screw driver slots, so I wasn't sure if I should trust them. I did see this in the manual:
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So I thought that the way the adjustments work would be a better indication if it was in the right position. Looking at the two valve adjusters on one side of the engine, the one on the left should increase the gap when turned clockwise, and the one on the right should increase the gap when turned counter clockwise. For instance, when working with the left side valves, the exhaust valve gap should increase with clockwise rotation, and the intake should increase with counterclockwise rotation. If you turn any of the in the increasing direction long enough, it starts to decrease again and the directions are now flipped. I figured if the directions are correct, the tick marks are in the right position. Is this a good assumption?
 
They appear to be pointing correctly. The marks aren't always bold and easily defined, but 3 of the 4 are obvious to me and the last one, left side intake, appears to be correct despite the mark being more off the usual location than I'm used to seeing. Realize that the adjustment could be achieved with them facing the opposite way, but the follower tip would be drawn away from the center of the valve stem when not properly oriented. Since the shaft is an eccentric, it will tighten and loosen in 2 positions but the proper orientation is the important part.
 
Don't know what happened to the images there. Basically the manual has two different values for the head bolts. One says 25 ft-lbs in the head installation section, but the table in the appendix says 32-39 ft lbs. I went with 35 because I saw the table first. Did I mess up a lot?
 
I've been looking around online and I'm starting to get really worried that I may have really messed up. What am I gonna need to replace because I've maybe over tightened?
 
what service manual are you using? Mine says


3. Install copper washers and cap nuts on the two right-hand
studs, and install flat washers and cap nuts on the other
studs, and torque the nuts.
Tightening torque: 350 kg-cm (25.3Ibs-ft)

NOTE: Tightening the nuts should be performed starting from the
inside and working outward in a criss-cross pattern by using
a torque wrench.

That said I think you should be fine at 35 as long as they're all torqued the same. The worse that could have happened is you squished down the gasket more than was needed.
If you do want to fix it though you'll need a new head gasket

 
Ok great, thanks so much. I did a bunch of googling yesterday and went right to worst case scenario. Thought maybe I ruined the studs or god forbid the threads. I'm definitely gonna replace the head gasket, I've already spent so much time on this I just want to do it right. Thanks for the reassurance. I was honestly terrified last night.
 
Hey ya'll! Engine is back together and on the bike and everything seems to be ok! Of course as soon as I get the engine on the bike, one of the spark plug boots falls off, and won't screw back in (seems like the wire is stripped).
PXL_20201113_231628140.jpg PXL_20201113_231634282.jpg
I checked online and it seems that the fix is just to snip off a quarter inch or so off the wire and screw it back in. Does that seem right?

I'm also about to get started finished with the ignition timing. I got the clearances set and it's not lining up (as expected). Any tips for this process?

Thanks!!
 
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