Shock absorber knocking

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camstevens
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Re: Shock absorber knocking

Postby camstevens » Tue Jun 04, 2019 8:32 pm

Hi All
OK, now seriously at my wits end and at the last throws of trying/testing things before disassembly of this new engine starts.

I ran the engine tonight with sealed collets, still the oil blues persist...I ran the engine with the tappet cover off, and there is no no visible over oiling at all. The blues are coming primarily (by far) from the right side pipe.I'm 99% sure now the oiling is coming from below, so may be a broken oil ring (can't hear that though) or perhaps a timing side bearing face is not sealing against the crankshaft properly? It's got to be something!!!!!!!

Only other symptoms i can see is there is more oil around the head gasket area on the right side compared to left. Not huge, but it's on the fins where the head/barrel interface and two fins down (guess it's leaking down stud threads and through the hole onto the fin below).

I guess I'm dragging this thread on, but I'm not into pulling something apart that's just gone together, at least not for no good reason. Any final suggestion before I go goo goo gaa gaa and start stripping back :roll:

Cheers
Cam

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Re: Shock absorber knocking

Postby Simon.Gardiner » Tue Jun 04, 2019 11:38 pm

Cam - has the left side settled down then, as you seem to have identified the problem now as being the right hand side?

SG
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Re: Shock absorber knocking

Postby camstevens » Wed Jun 05, 2019 5:29 am

Hi Simon
With respect to settling down, the left side head gasket has probably settled down in comparison to right, but given the level of oil burn (although the engine runs clean for 2-3 mins on start) I'm sure it's coming from below. The left side start to smoke (to a lesser degree) some time after the right starts blowing.........so, if I'm trying to apply some logic, the right cylinders are copping the oil first as it is next to oil pressure entry, with the left eventually getting the spillover the scavenger can't cope with. If it was a broken ring, only that side would smoke, so I'm guessing a plain bearing is not holding oil. The oil pressure is very high (>100 psi on startup) so I'll try a new relief spring a see if that helps, otherwise it's looking at exploratory by disassembly.

Regards
Cam

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Re: Shock absorber knocking

Postby Paul_Linden » Wed Jun 05, 2019 5:52 am

If it is a broken ring, then that would be just on one cylinder, and the spark plug on that cylinder would show a different colour?
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Re: Shock absorber knocking

Postby Gui.dorey » Wed Jun 05, 2019 6:29 am

Hello Cam,
Can you take a picture of the plugs? If a cylinder is burning oil one should be able to see it on the plug.
You probably checked, but are you sure all plugs are firing all the time? Although there were no apparent signs on mine, when I disassembled my engine I saw that Nr 2 hadn't been firing. When I had checked the spark before (hard to do as one has to hold it against the head and kick at the same time) I did get a spark, but likely it was just sporadicall or weak. Anyway, the cause was the old distributor cap, which wasn't good on that plug anymore.
Worth checking everything before tearing the engine down. Even if it seems unlikely.

Another idea - take the cover cap for the front crank off, and run the engine. Check if oil is coming out of the relief valve. At 100psi the valve should be opening and releasing oil.

You can also run the engine with the timing cover off and see how oil is flowing into the timing chest. Maybe you can find something out.

It still seems strange to me that something major is wrong on a newly assembled engine.
Best of luck,
Gui

camstevens
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Re: Shock absorber knocking

Postby camstevens » Wed Jun 05, 2019 6:59 am

Thanks
I agree....all of these things are worth checkingannd done most......all plugs are oiling to some degree, so probably the issue is common within the crankcase. I don't thing ignition problems would cause oiling?
Anyway, I'm probably becoming a nuisance on here, so will do another couple of final checks, then down she goes.

Cam

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Re: Shock absorber knocking

Postby john.whiting » Wed Jun 05, 2019 7:24 am

i think the bike needs a good run ,not continuous fiddling.......the exhaust and muffler will get a lot of liquid oil in them,and soon as they get hot,you will have bulk smoke ,no matter how little oil the motor is passing..............I had a V8 Dodge truck engine with one missing oil ring,and the plug on that cylinder would choke up with burnt oil.....not just a bit different shade....but black ,and the motor would start to miss if it idled for long periods.

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Re: Shock absorber knocking

Postby nevhunter » Wed Jun 05, 2019 9:22 am

An idling motor. like one going down hill with the throttle closed, will tend to suck oil up past the rings and down the inlet guides, because you have a high vaccum at idle. If you are getting very high oil pressure readings I would address that. It's far too high. then get it off the stand and on the road to allow things to settle down with a bit of load on the motor. End float on a plain bearing should not affect oil pressure. Having the two mainbearings plain on the rhs always has more oil about on that side Like a vertical twin which it's just two off coupled together. Nev

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Re: Shock absorber knocking

Postby chris.shearwood » Wed Jun 05, 2019 1:06 pm

Hi Cam,
I agree with John - I too think you should get on that bike and ride it. You mentioned using 40 weight oil - why not 50? Did you use running-in oil to seat the rings? My Sq4 could emit clouds of smoke right after its refurbishment but after a few hundred miles there was no trace of smoke.
Regards, Chris
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Re: Shock absorber knocking

Postby camstevens » Wed Jun 05, 2019 6:48 pm

Thanks, encouraging! Will give it a few road runs and hopefully end up in a better place :)

Cam


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