Topic: Paddy - '78 CB750 - Version 3.0 Coming Soon!

[theofam]

Anyone know why my 1 & 4 accelerator pump nozzles aren't getting fuel?  The fuel tube from carb 2 to 3 fills:



but the tubes from carb 2 to 1 and carb 3 to 4 stay dry:



As mentioned above, I had the carbs off the bike yesterday and the portions of the carbs that feed the accelerator pump's fuel tubes from carb to carb all flow fine when carb cleaner is shot through them.

In order to get fuel to the carbs, I was able to locate this magical petcock grommet this morning.  $10, and no petcock leaks anymore! 



I even bought a second grommet and dug through a tub of petcocks to find another CB, riveted petcock that I'll restore as a spare.

While I was at that shop, I also spent the best $7 of the project on this flasher.  I've somehow lost the right rear blinker, but the other three flashers are speedy and bright!

[theofam]

Nevermind. The accelerator pump fuel tubes appear to be filling up.

Paddy ran briefly with a massive gas puddle under the bike. His dope owner forgot to connect the fuel line and had the petcock on reserve!  I hope to get a video posted this afternoon or tomorrow!!

[theofam]

Almost done!

[MoMo]

Excellent, well worth the wait...Larry

[Stev-o]

Wow! You just might get nominated for BOTM! That paintwork and color are beautiful, polished motor covers and new exhaust gleaming, looking good man!

[theofam]

MoMo, glad you like it!

Stev-O, I can't believe you'd mention BOTM and Paddy in the same sentence!  Just suggesting it was good enough for me!

Today I need to replace the Helmet Holder stickers, polish up the front brake lever, give Paddy a minor bath/detail, and see if we're ready to ride!

I have visions of riding Paddy around Denver today thanking the various shops that have provided parts and services to help me out.  We'll see!!

[theofam]

The day was going great!  Paddy looked the business and all electrical, including the pesky right rear turn signal, was working.



He was starting a new life at this mileage:



I figured I'd run him over to my dad's house and then to the various folks who had helped me.  I had to pull over in the parking lot of the Honda dealership at mile 2.5 when I noticed what I figured was a terrible head gasket leak:



So, I beat feet home, hopped off the bike, cussed a bit, then started taking a closer look at this:



But guess what?!  There wasn't a drop of oil leaking anywhere!

Did I use the wrong paint?  Nope, it's engine paint meant to withstand temperature.  Really?  Even though the paint is bubbling?  With no oil leaks present, why would it bubble?  Maybe I exceeded the paint's heat threshold?  Nah, what would cause that?  Hmm . . . no . . . what your mind is saying can't be happening.

Do you have ANY oil to the top end?  I pulled a valve cover plug on #1 exhaust - BONE DRY!  Same on #4, BONE DRY!   

So, I just cooked my motor after a six-month rebuild.  Nice.  Have you ever been so pissed yet so disappointed that you merely exist in a sort of shoulder-slumped complacency?  That's where I'm at right now.  Unbelievable.

I guess this now starts Paddy's Rebuild 3.

[brandEn]

HOLY CRAP! So sorry to hear of this. I have been lurking on your build and this is horrible news. I can totally feel your pain and frustration. Hopefully its not as bad as what it appears. Hang in there buddy!

[theofam]

Thanks for the condolences, brandEn. I'm in a state of disbelief.

[knowsnothing]

  and Paddy 2 was so pretty and shiny.  That sucks man, sorry to hear it.  I wonder what the hell happened.....

[theofam]

Paddy 2 was pretty! Paddy 3 will be beautiful.

I'm questioning either the oil pump or an oil passage. I had the cases, cylinder and head media blasted in preparation for paint. It took a long time to clean out the various passages of the media. I suppose it's possible I missed a passage, though I thought I was very thorough.

I'm going to research engine removal methods that don't require an entire tear down again.  Once I figure out a plan of attack, I'll get back at it, but I'm going to step away for two weeks to regroup and enjoy my kids' Spring break.  If I go at it now, I'll sell him for scrap!

[liPPy]

Aw man, I'm so sorry

At first glance I thought "Wow - gold cylinder head, that's different!" then I read the post and saw why it was gold.

As I get closer to my K8 completion threads like yours keep me awake at night...

[tweakin]

Sorry to hear about your misfortune....that sucks!  What a beautiful build.  Take a brief break and then tear into it.

[Stev-o]

Very sorryto hear. May be time for an 836 kit?

[theofam]

Thanks fellas. Part of what has kept me focused has been your support throughout the build.  I'll get back at it, it's just tough to tear back into him after all that work.  836 doesn't sound too bad!  Can I run stock cam and carbs?  Stick with original studs or upgrade to APE?

[lucky]

How far did you ride?
What about your oil pressure gauge or oil pressure light? Are they showing oil pressure?

[Stev-o]

Yes, you can run stock carbs and cam, but head work would be a plus. Have you read about the cheap eBay 836 kit? There is a long thread about it, even Hondaman has used a couple.

http://www.ebay.com/itm/69-77-HONDA-CB750K-836cc-BIGBORE-PISTON-KIT-W-GASKET-/140697308917?pt=Motorcycles_Parts_Accessories&vxp=mtr&hash=item20c2368ef5#ht_1484wt_689

[theofam]

Thanks Stev-O, I'll check out the kit. I just had head work done. I'll see if it's salvageable.

Lucky, the oil pressure light illuminated when I turned on the ignition then turned off once the motor was running. Are you suggesting the oil pressure light is to remain illuminated at all times?

[MoMo]

Oil pressure light goes out wth proper pressure.  Did the motor start to lock up? Buy an oil pressure gauge with the proper fitting to verify the reading, and don't start it until then...Larry

[KB02]

How far did you ride?

It's a good question that still delivers some hope. Pull it down and measure away and see what you've got. You might be lucky. If not, I can only offer you this:
- Been there. Done that.
You certainly aren't the first this has happened to and you won't be the last.

The rest of the bike is gorgeous. I was planning on sending a BOTM nomination your way for it. It SHALL live to ride again!

[theofam]

The engine was starting to get sluggish, but it didn't lock up. Only so much I could ask of the 20/50 assembly lube I used!  Can't believe it lasted the 5-minute warm up and 5-mile ride. All told, Paddy ran 15 minutes today and 2-3 minutes yesterday.

I was just wondering if I'll need to split the cases again. Guess I'll know upon tear down.

KB02, you're too kind for suggesting a BOTM nomination. That certainly motivates me to get Paddy 3 back up and running!

[LesterPiglet]

Sorry for your trouble theofam, that's a lovely bike. Not being funny, I like the gold on the engine tho.

[cwchan]

There may be hope.  Looks like some others have had a similar prob.  The brown may fade...

http://forums.sohc4.net/index.php?topic=82531.150

[SOHC Digger]

I just had the identically same problem, complete with gold cylinder head!  The problem?  Clogged oil oriface under the 1-2 cam tower.  The rest of the engine was fortunately untouched.  I was able to replace the cam, tower, rockers, and oriface, clean up the area, and reassemble.  I am willing to bet this is your problem too.

That sucks, but if it's all it is, it could have been worse!

[cben750f0]

is it making an awe full rattly noise?,  loosen off the rockers and see if there is excessive play in the rocker arms, is there metal in your oil, did you prime the oil pump before you started? check the oil, pull the plugs, turn the motor over, you might have dodged a bullet.... dont psych out, start at the start and check everything again, it might be that the pump isnt primed.


just a thought, i do feel really bad for you though, cos its a bloody beautifull bike.

peace