Author Topic: She's bleedin' UPDATE: NEED HELP! (Read 3244 times)

canonball · « **on:** February 27, 2014, 09:40:58 PM »

So I went riding around the other night and on my way back home I got pulled over for not having a license plate, or so thought the officer who puller me over (my plate is angled a bit and apparently becomes invisible at night). He was cool though, let me off with a warning, but while I was waiting there I noticed the block looked wet and after taking a closer look I could see it was leaking oil and then noticed my pant leg that had oil splatters all over it. I got it home and took a couple quick photos to send to a buddy and figured I'd post them up here for opinions. Looks like possibly a cylinder head leak? Maybe a new gasket would be the solution? I keep the bike parked at in the parking garage downstairs for my building so I can't do any major repairs here at my place but I'd like to avoid leaving it at a shop (and spending extra money that I may not need to). Anyway, just thought I'd see what you guys think from my not-so-informational photos, it looks like it's on the right side mostly (right side if you're sitting on the bike) and dripping down the fins... and then onto my pant leg... if that helps at all.

Sorry for the sideways photos, if you click on them they show up the right way.

750K · « **Reply #1 on:** February 27, 2014, 10:59:23 PM »

If it were me I'd clean all the oil off and fire it up and see if the oil leak shows itself, while riding oil will blow all over the place making it hard to really track down the exact spot. Before the top end was rebuilt my 77 was leaking from almost everywhere, left stains ony pant leg.

martin99 · « **Reply #2 on:** February 27, 2014, 11:11:43 PM »

+1
Clean it up, squirt some baby powder around there and you'll be able to pinpoint the leak.

AJK · « **Reply #3 on:** February 27, 2014, 11:52:07 PM »

my guess is that its a leaking rubber puck making a mess of the whole show. With the engine running, try and peep in the cylinder fins between the exhaust pipes and see if you can see a small stream of oil coming out. Use a strong torch.
I'll try and post a pic of where i'm talking about soon.

[update] - I've attached 2 pics, shining a torch down on an old head down the puck hole. In the 2nd pic you can see where abouts you need to look through. Note, that if this is your problem, you should be able to see a slow stream of oil emerge out of that area, but it may take a few minutes of running time before it starts to pool up then overflow out of that section, so allow for that.

Assuming this is the source of your problem, there are 6 pucks, so you will need to isolate which one it is.

Also, Hondaman makes a little mention of leaking pucks on this page.
http://forums.sohc4.net/index.php?topic=115057.0

seanbarney41 · « **Reply #4 on:** February 28, 2014, 02:56:20 AM »

Just noticed in your second pic, that it is really oily up by your tach drive/cable. In my experience, bad leaks are always the pucks and I have not seen a tach drive seal leak that bad, but it is the only one you can replace with the motor in situ. ...so it makes sense to check into it more thoroughly.

canonball · « **Reply #5 on:** February 28, 2014, 06:56:17 AM »

Cool thanks for the info guys, I'll give this a try this weekend and see what I can find.

NobleHops · « **Reply #6 on:** February 28, 2014, 07:53:14 AM »

Spray "powder' deodorant is an option if you can't get the baby powder where you need it.

Trad · « **Reply #7 on:** February 28, 2014, 08:10:31 AM »

I too foresee this being a leak from one or many of the 6 rubber pucks. Honda part number 91318-300-013. Could also be the valve cover gasket, tach drive, or tappet cover gaskets. A leak this big is likely the sealing rubbers though.

Use a smear of gasket sealant on the bottom of each rubber.

canonball · « **Reply #8 on:** March 07, 2014, 07:30:32 PM »

Haven't had a chance to look into it more yet but I had a question about replacing the pucks if that turns out to be the issue. Does that require pulling the motor? If that's the case I'll have to bring it in to a shop since I don't have any sort of workspace at my place of residence at the moment. Just curious.

mcswny · « **Reply #9 on:** March 07, 2014, 07:44:01 PM »

Quote from: canonball on March 07, 2014, 07:30:32 PM

Haven't had a chance to look into it more yet but I had a question about replacing the pucks if that turns out to be the issue. Does that require pulling the motor? If that's the case I'll have to bring it in to a shop since I don't have any sort of workspace at my place of residence at the moment. Just curious.

If it's a 750 the. Yeah unfortunately you're going to have to pull the engine. Could you pull it and work in your house/apartment? Can't imagine what a shop would charge you for that.

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mcswny · « **Reply #10 on:** March 07, 2014, 07:47:13 PM »

But like prior posters have said, clean it an put baby powder on it first to find the leak. There's a lot of oil up neat the valve cover gasket and tach seal.

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canonball · « **Reply #11 on:** March 07, 2014, 07:52:50 PM »

I'm on the 6th floor of my apartment building so no dice getting it inside the apartment. I'll definitley check it out in more detail before bringing it in somewhere and probably post up here what I found.

mcswny · « **Reply #12 on:** March 07, 2014, 07:56:20 PM »

Quote from: canonball on March 07, 2014, 07:52:50 PM

I'm on the 6th floor of my apartment building so no dice getting it inside the apartment. I'll definitley check it out in more detail before bringing it in somewhere and probably post up here what I found.

Ahh bummer, hope it works out.

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mrbreeze · « **Reply #13 on:** March 07, 2014, 07:56:59 PM »

I had to go back and see what bike you have. I see it's a 750 so yes.....motor has to come out...UNLESS!!.............you go with a Gordon frame kit. I think I just read about someone getting a batch together. If you woulda had one of the smaller bikes it could be done with motor in frame and this is what the Gordon kit is for. My K5 is getting the weep going on but not anywhere close to really dripping. So with the 750 and no real place to work on it.........you can give your cash to the shop you take it to or you can buy the kit and give some cash to a good welder to install it. Then the next time you have to go into the top end you can do it in the frame.

Trad · « **Reply #14 on:** March 07, 2014, 08:53:38 PM »

Quote from: mrbreeze on March 07, 2014, 07:56:59 PM

I had to go back and see what bike you have. I see it's a 750 so yes.....motor has to come out...UNLESS!!.............you go with a Gordon frame kit. I think I just read about someone getting a batch together. If you woulda had one of the smaller bikes it could be done with motor in frame and this is what the Gordon kit is for. My K5 is getting the weep going on but not anywhere close to really dripping. So with the 750 and no real place to work on it.........you can give your cash to the shop you take it to or you can buy the kit and give some cash to a good welder to install it. Then the next time you have to go into the top end you can do it in the frame.

As much as I love 750's, pulling the engine to do any top end work is such a headache. The Gordon Kit is a must IMO if you plan on doing any kind of real tuning.

Good luck with getting the repair fixed up, it's an easy job once you can get the valve cover off and in there.

canonball · « **Reply #15 on:** March 16, 2014, 12:36:22 PM »

So I've got a workspace figured out, found someone with garage space they're going to let me use to fix the bike. Also it's been so long since I've taken the tank off I forgot the PO did hack up the frame, I was kinda pissed when I found out after getting the bike home but now it may save me from pulling the motor (fingers crossed!). I took this a while back not too long after buying the bike...

martin99 · « **Reply #16 on:** March 16, 2014, 01:59:25 PM »

That's a different approach to a frame kit that's for sure, but it doesn't actually look too hacked to me. Quite the opposite, there's a bit of thought gone into that. At least it's better than nothing

Can't really tell from the pic, but if the tubes that slide over the frame rails are bolted in place it may even have a bit of strength to it. The PO might just have saved you a lot of grief.

canonball · « **Reply #17 on:** March 22, 2014, 01:30:29 PM »

I'm getting ready to take it down to a garage someone has kindly offered to me. Sounds like one or more of the puck seals are most likely the issue, I was reading through the clymer manual and it looks like I'll need to remove the valve cover as well as the cylinder head in order to replace them. I should probably replace the valve cover and cylinder head gaskets before putting it back together right? Any other seals/gaskets/parts I should replace along the way? Someone told me to check the rocker arms while I was in there, what exactly would I be looking for as far as wear? I've never done any internal engine work so this will be a total learning experience for me

Edit: I fired her up and let her run for a few minutes and I could see where the area where the oil is leaking from and from what you guys are saying I could see this being a puck issue. I took a couple photos and one of the diagram in the clymer manual where it looks like the pucks are (on the 6 cylinder head nuts right?). The oil is coming from right around where the number 12 nut is on the top-right of the diagram. Am I thinking about this the right way?

AJK · « **Reply #18 on:** March 22, 2014, 06:03:40 PM »

To repair the puck leaks, you will need to remove the following:
- motor from frame, rocker cover, camshaft, cam sprocket & rocker shaft assembly. Once you take the rocker assembly off, you will get access to the 6 x rubber pucks that lay underneath and you will immediately locate which one was the culprit.

I wouldn't replace the head-gasket if it doesn't need replacing, however I would re-torque the head nuts to 19 ft.lb while everything is apart since this is a good opportunity to do so.

If your've decided to replace the head-gasket, then make sure that after you torque it back up, to leave it over night so it settles, then re-torque it in the morning before re-installing your rocker gear.

Important to remember the small o-rings that sit beneath the rocker assembly for the oil feed. Don't forget those!

Ensure your valve timing is set-up correctly when reassembling your cam.

mcswny · « **Reply #19 on:** March 23, 2014, 08:06:00 AM »

This is all very easy and if that is a frame kit you don't even have to take your engine out. I

I would definitely consider getting Hondamans book. I did a top end rebuild this winter with no reall engine knowledge and his book is worth it's weight in gold. Seriously the $100 price is pennies compared to what it's worth.

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mcswny · « **Reply #20 on:** March 23, 2014, 08:11:52 AM »

Go to www.lulu.com and search for "My CB750 Book" to find it.

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flybox1 · « **Reply #21 on:** March 23, 2014, 08:29:26 AM »

Quote from: canonball on March 22, 2014, 01:30:29 PM

I'm getting ready to take it down to a garage someone has kindly offered to me. Sounds like one or more of the puck seals are most likely the issue, I was reading through the clymer manual and it looks like I'll need to remove the valve cover as well as the cylinder head in order to replace them. I should probably replace the valve cover and cylinder head gaskets before putting it back together right? Any other seals/gaskets/parts I should replace along the way? Someone told me to check the rocker arms while I was in there, what exactly would I be looking for as far as wear? I've never done any internal engine work so this will be a total learning experience for me

Edit: I fired her up and let her run for a few minutes and I could see where the area where the oil is leaking from and from what you guys are saying I could see this being a puck issue. I took a couple photos and one of the diagram in the clymer manual where it looks like the pucks are (on the 6 cylinder head nuts right?). The oil is coming from right around where the number 12 nut is on the top-right of the diagram. Am I thinking about this the right way?

AJK is right on the process to get at the pucks. Keep all your rockers and shafts together in sets. Don't mix them up.
Apply a thin layer of Permatex 2 or hylomar blue to the pucks at their edges before resealing.
And look for brandEns thread 'leak free top end'
Good info there.

canonball · « **Reply #22 on:** March 28, 2014, 08:00:57 AM »

Thanks for all the info/help guys! I finally got the bike down to a friends garage and started tearing it apart. I didn't have a whole lot of time so we got down to the cylinder head so when i go back I'll get the head off and take a look at the seals and see if I can't figure out whats going on. I think I'm just going to order a whole top end gasket set and replace everything as I put it back together, just to avoid another seal going bad in the near future. I've had the bike for almost two years and I have no clue what kind of maintenance was done in the 18,000 miles before I got my hands on it. Anyway, I'm sure I'll be back on here soon with more questions about this lol I took a few snaps before I left the other night...

p.s. the frame kit sure saved a hell of a lot of work since I didn't have to pull the motor!

Duanob · « **Reply #23 on:** March 28, 2014, 08:28:18 AM »

As long as you're down this far, why not do a top end? Johnny's Auto Sport in Ballard does a great job at refurbishing heads if you don't have the tools, time, or experience for a couple hundred bucks. Just don't tell them you're not in a hurry, make sure you let them know you want it back ASAP.

I have no experience with the 750 but I would buy an OEM head gasket and for everything else a good quality gasket kit should be good enough. And ditto on using a good sealant on the pucks. I even use permatex copper spray on the head gasket. Nothing more frustrating than having leaks right after doing a top end.

Just curious what part of town are you in?

canonball · « **Reply #24 on:** March 28, 2014, 08:49:45 AM »

Thanks for the tip, I'll keep that in mind! I'm going to add sealant to my shopping list as well. I'm in Capitol Hill, you?

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Author Topic: She's bleedin' UPDATE: NEED HELP! (Read 3244 times)

AJK

AJK