Hi all.
I've got an '82 80 cube shovel with 3/5/8 bore (zel barrels and S & S pistons) in a trike that weighs 440kg. A compression test comes up with 150psi on both cyls. Is this too high?
Thanks, Rick.
Thanks. 160 hot. I was thinking that was too high. Doesn't pre-ignite on premium though. Don't know about 91 octane. I should try it.
My wife, my young bloke and I had a trailer behind our trike and were on our way from sydney to brisbane for the imbil rally. We got as far as Karuah when I thought I heard pre-ignition under load. Over the next 20 or so k's it seemed to get worse, so I pulled over. Sounded like too much valve clearance, or perhaps rings floating around on the piston. The oil tank was too hot to touch. I checked none of the lock nuts on the solid lifters had come loose. Checked the primary chain (getting desperate now), all looked good. I trailered it home back to sydney.
Got home, did a cold compression test, 150psi. As good as new.
Started it to warm it up, no noise. As it got hot, the noise began to come back. Listening with a screwdriver, it seems to be coming from the head and rocker cover. Perhaps the valve clearance has opened up. I did set them fairly loose. Perhaps too loose, and they may have worn when it got hot. I was sitting on 70mph when the noise started, and it does weigh in at 850kg with the trailer and us 3 on it.
So now I'm waiting for it to cool down so I can do the valve clearance again, this time so the pushrods have no movement other than turning freely. The top end is only1500 K's old, so fingers crossed!
What's the best oil cooler to run? Does anybody make one with a thermostat? I was told I don't need an oil cooler by someone who builds engines professionally, but after feeling the oil tank get so hot, I'd feel better if I had one.
Checked your timing? is it too far advanced, would cause it to pink under load and run hot, what did your plugs look like, when you had the top end done did you shave the heads, what compression ratio are the pistons. is it running lean. a lot of variables.
I checked the timing at the 1000km service (morris magneto). Was good.
The plugs look tan inside and around the electrode, with the outer edge where the thread ends slightly darker. Looks good.
Jetting, it has an S&S B series, and I tried main jets from 170 through to 184. I settled on 174 as it runs the best time on a top gear roll on from 55 to 70mph.
Compression ratio I couldn't tell you. It's running zel barrels and s&s pistons. I haven't shaved the heads, but I know the valves and seats are new, the ports have been welded and re-shaped, and the head was bored to suit the 3 5/8" dia pistons and barrels. I couldn't tell you what cam is in it, but I can tell you it runs solids, the springs and valve caps aren't standard, and the rocker covers have been ground out to clear the valve caps. The heads have had steel o-ring inserts on the gasket face, and the oil return holes have been welded and moved to suit the bigger barrels.
What I can tell you about the compression ratio is that I've never heard it ping before, and I'm fairly certain that if it was pinging I heard when it shat, it was probably cause it got so bloody hot. I couldn't touch the oil tank. This motor is happy as a pig in pooh when I'm riding solo, but put three of us and a loaded trailer on it, it aint so happy. I bought it to tow a trailer, so I've got to try to sort it. It did get hot, so I'm hoping an oil cooler will help......Lots. Which one do I buy?
Having a trike your going to be able to hide a cooler anywhere, i`d use a car transmission cooler with a filter before it and a thermostat so it don`t get too cold. Sounds like you got all the good gear on it.
and check your messages i sent you a site
hi, i would use prem fuel only because the comp would be higher than a normal shovel because of the big bore , + you would have to bring the timing back a little compared to stock spec , the magie is full advance type only ? re-set the timing a few deg's retarded so the full adv timing mark is just forward of the timing window about where the thread for the window is thats about 2 1/2 to 3 deg's,
on a shovel always check the cam follower wheels if they haven't been replaced check on them ?, or rattle could be solid insert coming loose if not a tight fit, very early pan tappets are solid one piece thats what i use or weld the insert to the cam follower & grind it back just tape up the wheel & wash-out good ,
set tappet adjustment , just over TDC on the comp stroke & adj both & then do the other cly, but check 1st the cam follower wheel s , are you using 50/70 engine oil ? cheers
Hi again.
I've been away with work for a while, so I haven't been online. Thanks for your help earlier houli. It was much appreciated.
Daddyracer56, thank you too. I only run premium unleaded in my harley. Being a shovel trike, it's working fairly hard. I only bought it in August, and it's been a steep learning curve.
The followers checked out OK, so I pulled the heads off and found the bores were scored. I pulled it down further, and found the crank bearing on the rear rod had failed. I was lucky I pulled it down before it let go. After finding that, I figured I'd better get back to work to pay for the angry old turd of a thing. I haven't stopped since.
I ran Nulon 20/50 oil in it while it lasted. I only rode it about 5000 k's till it grenaded. It wasn't right from the start. Always metal in the oil.
When I first bought it I took the heads off to replace the rocker cover gaskets. The barrels were slightly scored then, so I honed and re-ringed it while I was there. It was then I noticed metal filings stuck in the piston skirts. I figured it may be metal off the cylinders, and that it may have got hot at some stage. The pistons and bores measured up within specs after a hone and cleanup, so I re-ringed it and put it back together. When I pulled it down this time (1500km later) the pistons had more of the same metal in them, metal fron the crank pin and bearing. The crank was buggered when I bought it. I'll let you know how it goes.
Thanks,
Rick.
hi. sorry to here that , you have to use 50/70 grade oil in pre evo's , shovel/pan/kunckle , cast iron sporty, penrite make a H.D.oil for early harleys 50/70 straight engine oil , when you rebuild the engine make sure you replace the oil lines , & clean the oil tank-out proper esp under the filter cap lid inner lip if you run your finger in & around the inner lip you will get metal filings this is the 1st place to look at when buying a shovel . good with the rebuild ,
