Another lesson in how NOT to build a BBB

great news i guess. i hope every thing works out for ya.

 

Fwiw - brazing works well in repairing sheet metal stuff.

Seems to be more vibration resistant.

Once upon a time I owned a BSA Alloy Clipper - a 500 CC single built for the Six Days Trial in Europe and the UK.

Rare bike nowadays, but what I want to point out is the exhaust bracket is welded to the pipe and bolted directly to the frame right behind the approx 180 degree initial bend.
It would break at the weld due to vibration of the solidly mounted engine and also due to thermal cycling.

I took it to a local muffler shop and the guy told me that brazing the bracket to the pipe would stop the breaking.
He brazed it and no more problems.

Trouble nowadays is that many look upon brazing as an amateur technique, but it's the way to go for a lot of things.

If you overlap a piece of 1" x 1/8" strap steel 1" with a similar piece, braze them together and put them in a tensioning test machine the steel will pull apart before the brazed joint does....

 

I bought a low mileage 455 20 yrs. ago that had an awful noise like a rod bearing. Turned out it was just the windage tray flapping around. Put a washers on the windage tray bolts and it still runs today!

Another one I bought was a fresh rebuild the had bearing shells missing from one crank journal!!! Dead knock and practically no oil pressure even with HV pump!!!:spank: ou: :eek2:

 

That`s great news.

 

I've been following this thread........and I'm glad you found the problem. :TU:

But this led me to a thought.......did you have the rotating assembly balanced? I would be inclined to think that excess vibration might be causing the metal crack like that. I see that happen from vibration on cheap lawn tractors all the time. Just a thought. :idea2:

 

Thanks for thinking about me. The rotating assembly was balanced and she ran smooth. I did order another used windage tray from Greg Gessler this morning. He told me he's had a lot of trouble with them breaking. I may fabricate a stronger one. If I like it I'll use it and post some pics.

 

take thais as a good lesson in advice 101:Smarty: always go with your own gut feeling. it generally won't steer you wrong. I'm glad it is a small issue and a cheap fix

 

well as of last night she's live again. I decided not to fabricate a new windage tray as the one I bought looked very nice and I believe I may be to blame for the failure of the old one. I remember visually checking rod to windage tray clearance on rods 7 and 8. Lots of room. Not wanting to turn the motor and lose the cam/lifter lube I ASSuMEd rods 5 and 6 would be fine. When I adjusted the valves I had to turn the motor. Again, I was so worried about the cam that I used those two revolutions to check rod to oil pan clearance. I did have to clearance the oil pan but I didn't ever check rods 5 and 6 and I think they ended up hitting the windage tray and breaking it. I did space this second windage tray away from the crank with three 1/4" washers on each bolt. Plenty of room now.

When I had the engine on the stand I used a garden sprayer with clean kerosene in it to clean the crankcase, and its contents, and the valve/head area. That worked like a charm. The kerosene then just dripped into the pan on the stand under the engine.

After it was reinstalled :spank: I fired the engine for 1 min and changed the oil and inspected/cleaned the system one oil filter. I did this four times with a gallon of oil each time. The trash I found was maybe 66% less with each oil change and I found nothing on the last one. I so hope there are no future problemsray: ray: ray:


lesson learned: Check ALL! rotating clearances, even the windage tray, before you install the cam for the final time with the assembly lube.

I'll tell ya, I'd pay double for a new pre broken in cam and lifters. It would save a lot of time and worrying for me anyway. No valve spring changes. No special lube. Turn the motor all you want. No 20 min break in.

 

Some lessons are painful but I'm glad nothing major was wrong, you should be good for many years of tire melting grunt now.

Steve

 

I think a roller cam requires no break-in...

-Bob C.

 

I learned the hard way about windage trays.....Dropped a newly rebuilt 455 in my car, and found out that the dipstick was hitting the windage tray....had to pull it and fix it....not fun.ou:

ALWAYS check fit and clearances!

 

A lot of folks are breaking in fairly strong cams by removing the inner valve spring then doing the 20 minute 2000 rpm run-in.

Then the inner spring goes back in.

Fairly common with the drag race contingent....

 

You think correctly:grin:

 

I'm not sure all is fine with this engine. I am watching the oil closely.

Is a roller cam a drop in replacement or are there other concerns and mods that need to be done?

 

You'll find the expense not worth the effort with the roller cams unless you're at a very high level of build. Not only is the camshaft and lifters expensive, but if you're going with aggressive lobe profiles you'll need a lifter bore girdle. Then a button to keep the camshaft from walking. Which is just a simple addition to the front cover but its something you'd have to fab up after measuring. New pushrods for the correct length & then a cam/dist. gear oiler. You can easily have over $1,500 in a roller setup.
Much less hassle with a flat tappet design with performance very close to a roller for even an aggressive street and strip setup. Just remove the inner spring, plenty of good lube on the wear surfaces, lots of zinc in a good quality oil and follow sound camshaft break in procedures.
But it is true a roller design needs no break in. The roller I put in mine was a custom design. Idles at around 800 rpm (still tuning the setup), with 12 to 13" of vacuum. It has 254/260 dur. at .050", .641"/.647" lift on 112 LSA. If I was to do it again I'd probably go with custom flat tappet something in the 308S area. Just to save the money.

 

I sure hate to bring this thread back up but I have problems. I pulled the engine last week to fix an oil pan leak. Today I was draining the system 1 oil filter and was surprised and pissed when I saw a bunch of copper in it ou: Off came the pan and I started pulling bearing caps. #2,3 and 4 mains are bad with #4 being the worst. The pic shows them in order left to right. The rod bearings are all perfect as are #1 and #5 mains. I had to put it away for now due to time but I wanted to post here and see what people thought may have caused this. My last oil change was 732 miles ago and the filter was clean. The engine ran strong and oil pressure was normal 65-70 psi @ 5000 and up and unchanged from when I first ran it July '07. I have pressure taps front and rear and there was a 5 psi difference always. Total mileage is around 4K. Clearances are .0025 mains and rods. It seems odd that only the middle three mains are bad and everything else is fine.

 

oh no!....... :ball:

It looks like lack of lubrication, however I don't race nor do I rebuild engines so wait for more experienced guys.

How was your oil pressure? what weight oil were you using to get that pressure? how do the holes in bearings line up with the oil passages in the block?

 

my first 455 had the same color bearings, till this day i know its still running, it has had a little over 800 miles since i saw the copper looking bearings, excuse my question but what exactly does a windage tray do. thanks

 

Bummer Andy,

What's the buildup specs?

Center 3 mains failed because they have a rod on each side of them, whereas the front and rear mains only have 1 rod (and the resulting loads) on them.

Lack of maintaining the wedge of oil is the issue here, breakdown of that caused bearing to journal contact, and the heat and surface damage of the bearings.

Many possible causes for this, so that's why I am curious as to how much pwr this was making.

JW

 

but what exactly does a windage tray do


a windage tray keeps oil in the bottom of the pan away from crank. otherwise, the crank can pull oil out of the pan and beat it around the galley, aerating it. it also functions as additional weight and drag on the crank.