No Oil pressure

[wayne]

I'm not far from slitting my wrists working on this bike so any help appreciated.

This is an almost complete ground up restoration. Every component except the proper unit itself has been stripped, hand cleaned in kerosene, sent away for various processes, hand cleaned on return and reassembled.

I started the bike about 2 weeks ago knowing that the oil pressure light didn't work. It was just a quick start to assure myself that everything else was about right. Started straight up, did about three 10 to 15 second runs.

Problem with oil pressure light traced to switch on pressure regulator. When I removed the switch I was intrigued to find no evidence of oil (other than assembly lubrication) in the regulator. Looking further, no oil in the oil filter nor in the oil cooler.

The oil pump drive shaft is also the points shaft. So it's definitely spinning otherwise there'd be no ignition. Pulled off the regulator, oil cooler and clutch cover. Disassembled the oil pump. Couldn't find anything amiss. The critical drive pin was there, all components assembled correctly, gasket in good shape. All oil passages clear (I poured oil through all of them) and painstakingly followed the oil path so I thoroughly understood where it's going and why.

Double checked the regulator and also note that if it fails, it won't actually stop oil flow, it'll just fail to bypass the cooler, bypass the cooler when it shouldn't or fail to protect from excessive oil pressure.

All reassembled, pump well oiled, even filled the filter with oil prior to reassembly. Started it up with a working oil pressure switch- Oil pressure light fails to go off. Let the bike run for 15 seconds and revved it a bit also. Pressure light remains on. Pulled off the oil filter, all the oil I'd primed it with is gone but no evidence of any oil entering the filter at all.

I started it again with the oil filter removed. No oil flow. Nothing.

Oil flow goes from the sump via the straight or "S" shaped filtered tube to an area just behind the large flanged bolt in the clutch cover found below the oil filter. It gets sucked up into the pump and is then sent first to the oil filter, regulator, cooler and finally the engine.

What the heck is going on. Cavitation ??

I've had all this stuff apart on another RE5 which had no problem pumping oil around the system on post assembly start up. I'm dubious about cavitation, and if so, how long can I run it with no oil flowing to the main bearings waiting for the pump to purge the air ?

Wayne

[wayne]

This is going to sound like a very sudden solution but I've been working on this for a fortnight.

I tried something radical.......I got a rubber stopper which was a tight fit in the standard oil filler/dipstick hole. Drilled it to allow my compressor fitting a snug fit.

Then I turned the compressor on at 20 psi with the oil filter off. I could feel air coming out of the filter outlet (ie air was flowing in reverse through the system). I then realised that there was no way that I'd get oil to flow in this manner as it wouldn't get through the pump but thought that it may force oil up the draw tube into the pump body. Would this then create a feed to the pump ?

I started the engine while running the compressor and have never been so happy to have oil gush out of the oil filter inlet and all over my shed floor.

Quick shutdown, oil filter back on, compressor unplugged, hit the starter and the oil pressure light goes out within a couple of seconds. Woo hooo !

I've never heard of anyone having this issue before but, despite oiling the pump components very well before assembly, it was unable to draw from the sump. I suspect that perhaps this pump is well worn. I didn't conduct the book test on pump tolerances.

Hopefully might help someone in the future.

Wayne

[FC Zach]

Remove the 21mm hex plug by the oil filter and remove the pick-up/strainer assembly and look to see if o-ring (part 15) is there. Don't look at the drawing too literally, the o-ring actually goes between the tube and engine casing.

Attachments:

[wayne]

Thanks Zach, and indeed it is in place. Also in the correct position. Interestingly its not been in the correct position when I received other bikes, somebody fooled by the parts book in the past. But a related problem now surfaces:

Happiness can be an ephemeral thing............

Yes the oil is flowing and the oil pressure light goes out as I was running it on choke. I then did the metering Oil pump test which requires 2000 rpm. All good. With the choke off and test over, I can reset the idle down to about 1500-1700 rpm. Then the oil pressure light comes on.

Basically, the oil pressure light is on whenever rpm falls below about 1800 rpm.

Guess I need to put a gauge on it to work out what's going on now.

Perhaps the oil pump is shagged and that's why it was unable to self prime in the first place.

Wayne

[ziggystardust]

Strange one Wayne, I'd be surprised if the oil pump was worn as there would have to be some serious neglect there in the past.

One thing you didn't mention regarding the oil pump assembly was if the inner and outer rotors were in place with the punch marked faces looking outward.
Fig.5.12 Oil pump section.

Searching for ideas now but are the rotors a set and not from different oil pumps?

Z

[wayne]

Ziggy, the rotors are, as far as I know, original equipment on this bike. However, the bike has had a hard life and has certainly been dismantled at least once in its life prior to this.

Both rotors are in the correct way with punch marked faces outwards. I too would be surprised if it was wear, but I'm not left with much to else to go on. I was very careful on original reassembly and when I dismantled it last week it only confirmed that everything seemed as it should be (frustratingly. I think I'd rather have found a seal in backwards or something else clear cut).

Every seal, O ring and gasket is new except for the one in the points case itself. But if that was faulty, I'd expect traces of oil in my points housing (I think).

One of my contacts down here has offered to lend me his RE5 oil pressure gauge to get a better idea of what's going on.

Thanks,
Wayne

[ziggystardust]

You say the engine has had a hard life, well assuming the quantity of fresh oil is correct as is the viscosity then it could possibly be bearing wear to the eccentric shaft, support bearings and rotor bearing.

The RE5 oil pressure gauge should help here providing you have the pressure to rpm figures at hand, I assume that is how it works?

If you should go along the route of slitting your wrists make sure the blade is clean and sharp.

Z

[mike500]

hi wayne it could be a faulty oil presure switch,we have had even brand new ones keep oil light on at tickover but go light goes out wen at a higher rpm changed pressure switch and everything was perfect.if you suspect oil pump try a thicker oil and if that cures it then it is 99% that its a weak oil pump thicker oil will give higher pressure regards mike

[steveuk]

Are you sure its not your pickup tube split or gotten crimped/squashed under the strainer at the end. whilst it was all in bits

[Al Corelli]

Check for the passages leading to the pump to make sure they are airtight. The pump may be cavitating and not able to pull a vacuum and lift oil.

If you slit your wrists, slice lengthwise. This way, the muscles wont be able to tense up and stop the bleeding.

Oh,, if you do slit your wrists....
Can I have your bike?

[wayne]

Thanks Steve, but the pickup tube is in perfect condition. The bike had no pickup tube at all on arrival and Jess supplied a nice used one. From my understanding of the system, a missing or damaged pickup tube will not affect the oil flow unless the tube itself is blocked (as you mention). I had the tube in my hand yesterday and it is still perfect. But keep the suggestions coming.

Mike, you could be right, it could be something as simple as the switch itself and interested to hear that you've seen this before. I'll have an oil gauge by the weekend so will try that to see the real picture. I hope that that might be the problem although the fact the pump wouldn't self prime has me concerned. In the meantime, I might try a switch from one of my other bikes. Will let you know.

Ziggy, I have the test procedure here somewhere and indeed it is rpm-pressure. Minimum of 70 psi at high rpm from memory, I'll have to look up the specs. The bike had a cracked tranny case from a broken chain, holes drilled in the frame for some reason which had allowed the frame to fill with considerable amounts of water. I thought my dog had puked in the shed as the smell was so bad after the putrid water starting dripping out. The bike had been stripped in the past, many, many bits missing, household silicon used as a sealant all over the place, radiator tube cracked....didn't really matter, all blocked up anyway.....wiring loom in tatters with homemade repairs etc etc.

However, on arrival after it had been sitting for at least several weeks, the seller fired it up from dead cold with a single kick (!). And no, didn't notice if had pressure then as he ran it for seconds and turned it off. And similarly, it fired instantly and started within seconds after the rebuild. Amazing considering I'd flooded the chambers with GTX and sealed it all up prior to cleaning and wire brushing the proper unit (and just let it drain naturally). So the engine seems good, but I just won't know 'till I get it on the street.

Al, I've checked all passages for blockages. For air tightness, I can only ensure the gaskets and seals are all in place and are all new. However, the nature of the problem does seem to indicate either a worn pump or an air leak somewhere. You'll have to fight the owner for this bike.....it's not mine. I'm doing someone a favour that I've regretted for some time. Me and my big mouth.

So is this the nature of true friends ? Give advice on how best to do it then hand me a clean sharp blade rather than talk me out of it ??

Wayne

[Al Corelli]

Yes, False friends would not tell you their true intentions...

Please keep us posted on this. Just found that the bike I just got has the oil light on and it won't go out while cranking..

No carb on it, so it won't start.

Good Luck.

[wayne]

Borrowed the oil pressure gauge:

1200 rpm = 0.3 kg/cm (minimum 0.5 kg/cm)

4000 rpm = 2.25 kg/cm (minimum 5 kg/cm)

So there is a problem. Somewhere. Not sure what to do next. Just can't believe that the pump is that worn but failing a sudden revelation, I'll have to remove the pump and do the book tolerance tests on it.

Find below why pulling the pump down (again) really doesn't appeal. It looks finished, but it just won't go away.

Wayne

[ziggystardust]

The bike looks good Wayne, hopefully the problem is the pump but failing that it could be more serious as mentioned in my earlier post and be the main bearing/s.

Z

[wayne]

Thanks Ziggy. I was discussing it this evening with Steve Phelps. I don't think Steve's on the board but he's fairly well known among Aussie RE5 owners as he does a lot of troubleshooting and setups for people. He too echoed your earlier comments regarding main bearings.................uughh.

We're going to try running a different regulator (simply as a "why not" idea, don't think it'll help) and then Steve is lending me an entire clutch cover with all bits in place to try another oil pump.

Will keep you posted.

Wayne