R100S Öldruck

[jogepek]

Hello Guys,
sorry that I'm writing in english because my german is not so good. I hope it's not problem!
I recently purchased a pretty good R100S and would have several questions.
The previous owner put the bike down in the mid-nineties in a relatively dry and warm garage after he tumbled with it. he has dismounted the battery and spilled all the fuel from the tank and the carbs.
I've washed out the engine with some diesel fuel and filled with new oil and new oil filter of course and same with the gearbox, rear drive and drive axle housing.
Than took apart the carbs and replaced the gaskets, sealing rings and the membranes to new ones.
The bike got new ignition wires with connectors and nos Bosch spark plugs. I set up the valve clearances (0.1 intake 0.2 exhaust) but I'm not sure that these are the correct values. The valve cover gaskets have been replaced.
The bike got an aftermarket rear brake disc and all the brake parts were took apart and cleaned. There were some stoppages at the rear master cylinder. All the brake pads have been replaced together with the brake fluids. Got new Continental tires too.
I've purchased a new battery and started the engine. It runs but after the first 2 km the oil pressure light started to burn. I stopped the engine and started 5 minutes later only at idle revolution. A few minutes later the control light started to burn again. I've withdraw the oil pressure sensor and screwed in a oil pressure gauge. My oil pressure is 8-10 bar @ 1500 1/min and higher at higher revolution. I think it's too high and the oil pressure valve should let the pressure @ ~5 bar. I'm curious about the normal oil pressure. Is the oil pressure valve malfunction an usual problem? How could I fix it? Is the valve repairable?
I'm using Castrol 20W50.


Here are some photos:
https://drive.google.com/folderview?...Wc&usp=sharing

Thank you for all your help in advance,

Laci from Budapest

 

[kurvenfieber]

Hi Laci.
The pressure is O.K. for a cold engine, with ca. 120° C it should stay around 3-4 bar.
What you describe looks like a damage in bearings (Pleuel), Oil pump, or a misfitted Oilfilter (which should also have less pressure when cold.
How much pressure do you have with warm engine?

 

[jogepek]

Hello Herbert,
thank you for the response. The values that i wrote have been measured at warm engine. So 6-8bar @ idle revolution and 10< @ higher revolution. Could it be due to a misfitted oil filter element???
Thanks,
Laci

 

[kurvenfieber]

I don´t think so, a misfitted Oilfilter will cause too low pressure, but without indicating it by the control light.
I only could imagine that the Ppressure meter is damaged.
With a warm motor it shouldn´t be so high.

 

[jogepek]

Hello,
I've checked the pressure indicator gauge with an air compressor that has an individual pressure gauge. The two values have been matching.
Don't you think that the pressure regulating valve is damaged? I have so much oil pressure that would be enough for a small village

cheers,
laci

 

[kurvenfieber]

This should be the only realistic diagnosis.
It´s not too heavy to remove the Bearing.
You´ll find a how to in the database.(WHB)
Good luck to you.

 

[kunzumla]

Hello,

I can not understand why the oil pressure is 8-10 bar at warm engine, but the oil pressure light comes up. This will come up around 0,5 bar, as i remember.
Oil pressure cold (10°C) is 8-10 bar at medium rpm
Oil pressure warm (100-120 °C) 2-4 bar medium rpm, at idle 0,5-1 bar.
These values are roughly.
Has your pressure gauge a scale in bar?
8-10 bar oil pressure with hot oil is not understandable for me from the oil circuit construction.

Regards
Kunzumla

 

[kurvenfieber]

That could be right, but the only possibility should be the the high pressure sec. valve mounted at the front.
The control light shouldn´t be lighting when more than 0,5 bar. Maybe it´s broken

 

[traebbe]

Hi Laci,

first of all congratulations to the nice bike, an Airline.
Then: is it really the oil-Lamp?
Sure the orange an not the red light?
On the first ride with my RT the red light comes up on every stop, so i first thinks, damn, now you got a wreck, but the oilpressure was ok.
So be sure, before you do anything else, that it's the orange light, that came up.
The lightning of the red (alternator) light at idle Revolution is normal.
Several guys hooked up on that mistake, me too.

 

[jogepek]

Dear Sirs,
thanks for all your comments.
When I first rode the bike the orange (not the red for the generator) light came out after ~1,5-2 kilometers. That's why I stopped the engine because I thought that the oil pressure is too low. I wanted to know that there's only an oil pressure sensor problem or more serious a real oil pressure problem. So I picked up an oil pressure gauge from a friend of mine and checked the real oil pressure on my bike. The gauge has also a bar and psi sclae but it doesn't matter. After I obsessed this kind of high values on my bike I compared the gauge with a known pressure rate (on my air compressor that provides 10bar and it' own gauge showed the same value like the oil pressure gauge). So the measured values should be true.
I think the too high oil pressure killed the sensor switch and this is the reason why it provides false signal. So I suppose there're two separate problems: one is the sensor problem caused by the too high oil pressure and the second problem is the oil pressure regulating sensor. One thing is important: the engine wasn't started for 20 years... There could be a stoppage somewhere around the valve.
Do you agree?

 

[jogepek]

 

[jogepek]

Hello,
does anybody know how comes the regulating valve out from the bearing housing?

thanks,
Laci

 

[MM]

Here you find a schema of the hydraulic lubricating system:
The limiting valve at the end of the pressure line should determine the pressure at about 5,0 bar.
With cold oil there will be more pressure until this valve does work.
If there is constantly more than 5 bar in the system you need to check the valve.
In your case it should be this one:



Open the hollow bolt (10), inside you find a spring (11) and the pressure piston (12) which should slide well in the bolt.
Maybe it stucks.

 

[jogepek]

Thanks, it was helpful.

 

[jogepek]

Hey Guys,
finally I took out the valve. Nothing extraordinary appears. How could I test it? I'll make an adapter and will connect the valve with the air compressor for testing. Do you think it's a good idea?
It seems that I have to buy a new gasket for the timing cover, a new timing chain and a new oil pressure sensor switch.
Do you know a good part source? I have purchased some thing from boxerparts.de but there might be better.

thanks,
laci

 

[MM]

I like to buy parts at Rabenbauer.
But there are several more like Bayer or Siebenrock or ...

Does the piston move gently in the tube?
If yes: the spring may only become softer with the years.
So the valve seems to be ok.

Only one more idea: the system pressure may not arrive at that valve because the way to it is blocked by a foreign particle in the oilway.
Perhaps your washing procedure caused this.

Good luck.

 

[cjm]

Since nobody mentioned it so far: you said you've been driving for around 2 kilometers before the light came on, then turned off the engine and started diagnosing. The oil won't be warm after two kilometers, though - that takes rather 10-20km - and since it appears to be normal that the measured oil pressure is substantially higher with cold oil...

(Which makes sense because the limiter valve is at the end while the sensor is further up-front of the system and the oil will lose pressure with each bearing it has to pass.)

Are you sure the oil was really warm?

Thanks,
--Christian

Edit: The cold oil will lose more pressure with each bearing it has to pass.

 

[jogepek]

Hello Christian,
thanks for the reply.
After I connected the pressure gauge in place of the sensor I started the bike and it ran for long time. I'm not sure that the temperature reached the normal level but the 10 bar at idle revolution seems to be too high. Isn't it?
I don't understand exactly what you wrote about the sensor. Is it normal when the light comes up at cold engine?

cheers,
Laci

 

[cjm]

After I connected the pressure gauge in place of the sensor I started the bike and it ran for long time. I'm not sure that the temperature reached the normal level but the 10 bar at idle revolution seems to be too high. Isn't it?

Running the engine while standing will heat up the oil in maybe 15-30 minutes (although be careful with this because the engine and/or components close to the engine will overheat eventually without any airflow from the front).

I'm not really an expert on the exact expected oil pressure so I'll leave this for others to comment but it does indeed seem a bit high for idle RPMs. Have you checked for any obstructions as suggested by MM?

I don't understand exactly what you wrote about the sensor. Is it normal when the light comes up at cold engine?

Absolutely not. The opposite is true: cold oil gives you a lot higher pressure at the sensor. Given the fact that you're measuring way more than 0.5 bar while the light is still on, I would say the sensor is toast (unless you had a cabling problem, shorting out the wire going to the sensor to ground).

What I intended to say is that the point where you measure the oil pressure is not the same point where the high pressure valve operates. There may well be a pressure difference between the two, thus the valve may open at 5 bar as it should but the pressure at the location of the sensor may be substantially higher. One reason would be cold oil and "tight" (read: good) bearings between sensor and valve. Another reason might be some dirt/particles blocking the oil flow after the sensor as MM suggested.

Have you seen the oil flow diagram posted earlier in the thread? It shows where the oil travels from pump via crankshaft, piston rods, etc. back to the sump. The obstruction (assuming you had warm oil) would be between the location of the sensor and the overpressure valve.

Thanks,
--Christian

 

[jogepek]

I have dismounted the regulating valve and the oil comes from the hole normally when I'm turning the crankshaft with the electric starter. So I don't think that there's something stoppage.
Now I made an adaptor for the valve and try to check when it opens outside the engine. But I'd need another valve for comparing with this... Does have anybody for sale?

cheers,
Laci

 

[MM]

A strange problem you have...

Concerning earlier asked questions:
Very cold oil may produce up to 5 bar at idle revolution and up to 10 at higher rotation.
When the oil reaches more than 80°C the pressure should be about 1 ... 2 bar at idle and max. 5 at higher revolution.

 

[jogepek]

right the problem is strange but will be resolved. Now I only need another valve. I'd take it if somebody had one.

 

[cjm]

A strange problem you have...

Concerning earlier asked questions:
Very cold oil may produce up to 5 bar at idle revolution and up to 10 at higher rotation.
When the oil reaches more than 80°C the pressure should be about 1 ... 2 bar at idle and max. 5 at higher revolution.

Just a hunch but... how much resistance does the oil filter add? Could it be possible that the bypass valve is open and the lack of oil filter resistance increases the idle pressure?

Now I made an adaptor for the valve and try to check when it opens outside the engine. But I'd need another valve for comparing with this... Does have anybody for sale?

Maybe you could turn off the compressor after it has charged up to some 8 bar or so, connect the valve with your adapter and let air flow through until the airflow just about stops, then look at the compressor's pressure gauge? The valve may not be airtight but it should be possibly to catch it when it's about to close (e.g. the sound of airflow doesn't change anymore and the pressure drops slower)

 

[jogepek]

Hey Guys,
I recently replaced the oil pressure valve with another one (I've purchased two used on ebay.de). The situaiton is still the same, too much oil pressure.
Here is the value (warm engine, idle speed). Any idea?

thanks,
Laci

 

[MM]

Meanwhile I found another information.
The spring inside the valve should have a length of 68 mm.

For pressure less than normal there are a lot of possible reasons.
But too high - I have no more ideas at the moment.

 

[jogepek]

Thanks Michael,
tomorrow i dismount the engine again and check the lenght of the spring.

many thanks,
laci

 

[jogepek]

Hello Guys,
I don't have idea what to do because everything seems to be fine
-I've checked the spring length it is 67 mm
-the oil goes through all the rocker arms
-the oil comes from the hole of the oil pressure regulating valve on the front crankshaft bearing house
-the pressure valve works only when the pressure is over 5 bar. The normal pressure should be max. 2 bar at idle speed (I found these measurement values on internet and Michael said the same) so in that case the regulating valve doesn't matter. My oil pressure at idle is ~7 bar.
-I have done the measurements with more gauges with the same result so the instrumets are good

laci

 

[MM]

If you have done everything well -and I have no doubt about that- there are only two reasons possible regarding physical rules.

1.
Anywhere in your oil circuit is a foreign particle which derates the flow (and consequently increases the pressure). At the end of the line (behind the particle) the pressure is low -because wasted- and the pressure valve does not work.

2.
The bearing clearances in your engine are very small. This causes little inner oil leackage and high pressure in the system.

 

[jogepek]

Hello Guys,
since replacing the oil regulating valve to other ones (I have checked the all three and all seems to be fine) didn't resolve the problem I started the disassembling my engine.
The first thing that I found is a piece of nylon in the oil pan. I don't know what's that but I didn't find other pieces of nylon at other parts of the engine.

I took down the head, the cylinder, the pistons and the connecting rods and checked the oil flow everywhere but everything seems to be normal.
Then I took the engine out of the frame and checked the oil pump behind the clutch. No foreign items and nothing abnormal is visible.
My all engine is like new everything are clean.



I have obsessed a small dot on the oil pump rotor. What does it mean? It was to the engine.




Do you have other ides what I should check until the engine is out from the frame? What are the normal clearances at the oil pump? I can't figure them out from the WHB.

thanks,
laci

 

[jogepek]

Hello Guys,
I just want to thank all your help with your helpful comments regarding my oil pressure problem. After taking apart the engine twice it seems to be fine. Now we are over 1500 kilometers together and I really love this bike.

Laci