Topic: Oil delivery problem after CB550 engine rebuild

[Nik-bot]

Hi All,

Over several years, I rebuilt a '78 CB550K engine as follows:

   a) Cases, Cylinder, and Transmission from my old '78 Honda CB550K
   b) Refurbished and Ported head from Cycle-X
   c) Crankshaft from salvage bike
   d) Rods from salvage bike
   d) Webcam 358a camshaft
   e) WiseCo 10:1 pistons, 1/2 oversized
   g) MotoWerks GP exhaust system
   h) Mikuni VM34 carbs x2

I finished this up last winter and then took the bike to a shop to have them do stuff brakes, tires, check/reset ignition timing, repair corroded fuse box. Picked it up a few weeks ago.

I made four break-in rides of 5, 5, 5, and 3 miles and observed the following:
  1) Clutch engagement at beginning of each gear slips
  2) I only know air-cooled bikes and compared to normal, this engine gets really hot
  3) At the end of each of those four rides, returning to idle, the oil pressure light came on

Attempting to troubleshoot:
  > Opened tappet covers 1 and 4, ran engine briefly. I expected oil to splash out but none did.
  > Checked oil level and it was above the max fill line. I siphoned some out and it was very dark and dirty. Also smelled like gasoline. I took out more than a pint and before it was at max fill line. There are a couple reasons why gas could be in oil, but none that are still issues.
  > Drained oil and checked oil pan. I found only one speck of metal flake. Oil screen is clean and unobstructed
  > Changed oil and filter, added zinc. Filled to halfway between fill lines on dipstick.

After the above, I started it up again, and still no oil splashing out from open tappet covers. Still getting hot on top-end too quickly (my subjective observation).

My questions:

 1) Shouldn't I expect to see oil flung around view tappet adjustment holes?
 2) If so, can you suggest what I should check next?

Hopefully this photos link works. Oil pan, metal flake, oil screen.
https://photos.app.goo.gl/E3PzJHXeo2T4UWwY6

[HondaMan]

Pull off that rocker cover and see if there's lots of oil lying in those nooks and crannies up there. If not, there's trouble in the oil ports up to the head, or in the oil pump - which may be in the pump, given your Oil Light ON issue?

It is possible to plug this engine's oil jets for the top end if the lower top-end gaskets were coated with some sort of sealant around those outer edges where the oil feeds go to the head. As the cylinder cover can be removed in-bike and has an O-ring seal, this is an easy check to do.

[bryanj]

Oil wont necessarily fling out but should be visible, with what you have spent i would also remove cam cover to check for certain.
The restrictor jets are inside the dowel locating barrells to crankcase and have tiny holes, silicone gasket or blasting media WILL clog the jets starving the cam and followers

[denward17]

The one thing that sticks out to me is you smell fuel in the oil.

That can only mean you are flooding fuel and gas is washing the rings, maybe.  Check your carbs.

[newday777]

Hi Nik
Reading this my 1st thought on your high heat motor on short rides is not a good sign along with you saying you aren't seeing oil flow in the tappet caps, was that the intake caps or the exhaust caps? Exhaust caps will have oil coming out as you run it and will tell you if it is dry or has oil in the top end.....
As Hondaman and bryanj point to oil restrictor jets possibly being plugged from excessive silicone sealant breaking off in the motor I went through your engine build thread in the project shop(which you left hanging in 2019)
http://forums.sohc4.net/index.php/topic,174051.msg2061366.html#msg2061366
You said you used the Loctite gasket maker to put the cases together with, I'm concerned also of plugged oil jets from some excess of it breaking off so if you have no oil in the pockets of the head when you pull the cam cover off, that's the 1st place to investigate. If they are plugged,  then you need to open up the motor and clear out the silicone and inspect the rest of the motor. I think you said early in your 1st post that this was your 1st build?

[Nik-bot]

Thanks everyone.

Yes, I was checking for oil at the exhaust tappets.

Yes, I'd earlier started a project thread for this but some family issues came up and I moth balled it for a couple years.

As for the fuel in the oil, immediately after finishing the motor, I'd put on the original rack of carbs that had been sitting for years. I was eager to hear the engine start but these carbs were pouring out gas. I didn't rebuild them because I had other carbs arriving soon anyway..  I'm guessing it is during this time that I introduced fuel to the oil

Most of you advised to pull rocker cover and check the oil ports so that's what I'll do next.

I'll report back after checking the top end. Thanks again.

[BomberMann650]

Is the hose attached to the pickup screen?

Its gotta be a rigid enough hose to pull vacuum without collapsing

[Nik-bot]

How's it look to everyone?

https://photos.app.goo.gl/gZSx6YDX162eDbGT7

https://photos.app.goo.gl/rbk1iNxtUuMfbkay8





P.S. I can't remember how to insert shared pics from google photos...

[MisterKnife]

Maybe it's just me, but compared to mine this doesn't hold a lot of oil in the baskets for the camshaft lobes.

[flatlander]

yes it should have more oil in there.
like this:

[Little_Phil]

Yes very little oil one side. Was it on the sidestand?

[dave500]

i think the oil in those cam dip bays looks ok?look close its just clean and clear new oil?the oil in these old air cooled always stinks,if youd run dry up top it wouldve #$%*ed up real quick man!dont add the clutch issue you might have with any oil pressure issues you might have,ill bet the oil pressure sender unit is #$%*ed if you reused the old one?

[Nik-bot]

I just reviewed my assembly checklist and see that I did not check off the "prime the oil pump" step before installing it. Would this lead to less than expected oil reaching up top?

I no longer have a center stand but I do use a brick to keep the bike almost level when parked at home.

[dave500]

if the oil light goes out the pump has primed.

[bryanj]

You should not need to prime the pump on a 500/550, i have only had 1 awkward one in 40 years

[Nik-bot]

Thanks, all.

Consensus is that I do not have enough oil reaching the camshaft. Oil pump is good since light goes off immediately upon start.

Looks like the only thing for me to do is check for obstructed oil passages by removing the cylinder head, is that right? no other options...

[dave500]

you could remove just the rocker cover,pull the spark plugs out and with kill switch off spin the motor over on the starter and observe if oil is coming out of both those passages,dont pull the head unless theres no oil flow.

[Nik-bot]

Great advice. I'll do that and report back.

[bryanj]

Just had a thought, if you take the end caps off the cam cover and the steel mounting brackets off oil should pour out of those bolt holes when you spin the engine over, its why there are soft alloy washers between he bracket and cover

[Nik-bot]

https://photos.app.goo.gl/pudfe93bV5XpfDwg9

Here are two videos, one from each side.

[dave500]

looks like left side is blocked?pull the head.

[bryanj]

There should be oil pouring out of the holes shown in the recesses at each end when oil light out, looks like you have an oil feed problem

[Nik-bot]

Hi All, I got some hours today...

Refresher: complete engine rebuild. about 20 break-in miles in, suspected low or no oil on top end. confirmed lack of oil delivery at camshaft by observing while cranking with cover removed. oil pressure light turns off immediately when starting or cranking the engine.

Today I removed the cylinder head and lifted the cylinders enough to access the oil restrictors. I pulled them and they are clear. I can blow air through them easily. The passages above them, in the cylinder, are clear and clean.

Could a blockage be above, in the cylinder head? If so, how should I go about determining this? Or blockage prior to the cylinder passages?

I have been very careful during this assembly but keep in mind this project is a first for me, so anything could have been done wrong...

I appreciate any suggestions, thank you!

[MauiK3]

I’ve been suffering a similar circumstance on my Z1 project. I’ve disassembled the engine and blown air through all passages looking for blockages AND places where oil may be going that it’s not intended to go such as a missing plug. Since your oil light goes out the problem is likely “downstream” of the oil light switch. Start tracking the passages for any signs of problems.

[Nik-bot]

Today I checked the cylinder head oil passages with compressed air and both sides are clear.

This is a diagram of the oil flow in this engine: https://photos.app.goo.gl/mjEnPoSsYZh73S2y9

Since oil pressure light is going off consistently, all is well up to the pump? Is this certain?

And all passages are clear through the cylinders, the restrictors, the cylinder head to the cam journals.

This would appear to leave only the Oil Filter (just replaced and problem remained), Main Gallery, and Crankshaft Bearing (please, no) stages.

Please suggest next troubleshooting steps, thank you.

D.