oil pressure

[brs127s]

Hey everyone...

I tried to restrict the oil going to the newly installed oil cooler, but I was not successful. I am beginning to suspect the oil pressure sending unit may have a pressure raating that is too high. When I finally gave up, I had the smallest restrictor(I believe the channel was 1/8 inch diameter, plus the hoses clamped shut, so there was no oil passing through the oil cooler, but pressure should have been normal at the switch. That is why I suspect the switch. Can anyone tell me the oil pressure specs for a 1983 GS850GL(D). I would like to know the normal oil pressure, and the pressure it takes to compress the switch and shut off the oil light.

[Anonymous]

The GS motors use low pressure oil delivery. My 81 GS1000G workshop manual has it at between 1.5psi and 7psi. Most motor cars run more like 80psi, and I have seen a Kawasaki spec of about 80psi as well, so the GS spec is very low indeed.

I imagine your 83 850 will be similarly low.


Kim

[gs650gt]

The GS motors use low pressure oil delivery. My 81 GS1000G workshop manual has it at between 1.5psi and 7psi. Most motor cars run more like 80psi, and I have seen a Kawasaki spec of about 80psi as well, so the GS spec is very low indeed.

I imagine your 83 850 will be similarly low.


Kim

does it have roller bearings or journal bearings? gs's with journal bearings (like gs650g) have high oil pressure, 43 to 78 psi

[brs127s]

Roller bearings.

I went to the local Autozone last night(believe it or not, they are open 24 hours) to see if they might have a switch to replace the one that came with the pressure switch housing adapter. It is a very common part. I have seen it on a late 60's Harley Electra-Glide, and other older cars. The guy at autozone said it looked like the switch from an older Chevy car with a V-8. He looked up a 66 Chevy Impala with a 427(7.0 Liter). He said it would have the same fitting for the wire. He got the part number, but what do you know, they don't have one at the store. He said he thought was set for about 20 lbs of pressure, but he wasn't sure. At 4 bucks, I was willing to give it a shot.

If I need to, I will put the original switch housing and switch in, check the pressure, and continue my search. Hopefully, I can find something without having to do this.

[gs650gt]

Roller bearings.

I went to the local Autozone last night(believe it or not, they are open 24 hours) to see if they might have a switch to replace the one that came with the pressure switch housing adapter. It is a very common part. I have seen it on a late 60's Harley Electra-Glide, and other older cars. The guy at autozone said it looked like the switch from an older Chevy car with a V-8. He looked up a 66 Chevy Impala with a 427(7.0 Liter). He said it would have the same fitting for the wire. He got the part number, but what do you know, they don't have one at the store. He said he thought was set for about 20 lbs of pressure, but he wasn't sure. At 4 bucks, I was willing to give it a shot.

If I need to, I will put the original switch housing and switch in, check the pressure, and continue my search. Hopefully, I can find something without having to do this.

At least 0,1 kg/cm2.

I found this information from http://ezwebz.com/gs-classic/

[Anonymous]

Roller bearings.

I went to the local Autozone last night(believe it or not, they are open 24 hours) to see if they might have a switch to replace the one that came with the pressure switch housing adapter. It is a very common part. I have seen it on a late 60's Harley Electra-Glide, and other older cars. The guy at autozone said it looked like the switch from an older Chevy car with a V-8. He looked up a 66 Chevy Impala with a 427(7.0 Liter). He said it would have the same fitting for the wire. He got the part number, but what do you know, they don't have one at the store. He said he thought was set for about 20 lbs of pressure, but he wasn't sure. At 4 bucks, I was willing to give it a shot.

If I need to, I will put the original switch housing and switch in, check the pressure, and continue my search. Hopefully, I can find something without having to do this.

At least 0,1 kg/cm2.

I found this information from http://ezwebz.com/gs-classic/

does it have metric threads???

[brs127s]

Scotty,
No, it does not have metric threads. I believe when the adapter was made, the manufacture taped the side for 1/4 inch Standard threads. There is a 90 degree brass elbow coming off the side, and the new pressure switch screws into the elbow.

[brs127s]

I just got off the phone with Suzuki of America. They could not tell me pressure rating of the switch, but they did tell me that there was 7.1 psi at 3000 rpm.

[SqDancerLynn1]

I would maybe try some type of fuel pressure switch for carb not fuel inj
usually 5lbs you maybe able to get adjustable one from Holley or ??

[Hap Call]

I just got off the phone with Suzuki of America. They could not tell me pressure rating of the switch, but they did tell me that there was 7.1 psi at 3000 rpm.

Brandon, that 7.1 psi may be kind of optimistic...I looked in Clymer's (Al, I will get it to you one of these days!) and they stated the 2-valve GS750 (very similar to the GS850) had only 1.42 PSI (0.1 kg/cm squared) at 3000 RPM. My GS1100E only puts out about 3 to 4 PSI at 3000 RPM when it is hot and I even have the high volume/pressure oil gears that increase the flow through my bike by about 25%.

There is a chrome oil galley plug on the right side of the motor. When you look at the clutch cover it is at 2 o'clock, just below the cylinders. This is your main oil pressure galley. If you pull this plug (it screws outs with a 15 or 17 mm wrench), drill a hole in it and tap it to 1/4" NPT (national pipe thread) you can mount a gauge on it. The gauge should be no more than 15 PSI preferably 10 PSI. Run the motor with the old switch and record what you get to get a baseline. Next put the new set up on there and record what you get. It may not be a big difference!

I think I may have a spare oil galley plug in my small pile of spare parts. I will find it and have it drilled and send it to you. I really want to see this working right for you!

Hap

[Anonymous]

The GS motors use low pressure oil delivery. My 81 GS1000G workshop manual has it at between 1.5psi and 7psi. Most motor cars run more like 80psi, and I have seen a Kawasaki spec of about 80psi as well, so the GS spec is very low indeed.

I imagine your 83 850 will be similarly low.


Kim

does it have roller bearings or journal bearings? gs's with journal bearings (like gs650g) have high oil pressure, 43 to 78 psi

I thought the 850 was pretty much a smaller 1000 motor, but I've done some reading around the site and found that some things of the 850 match the 1000 with roller bearings, and other things match the 750 with journals. Which bits match which motor are probably stored away in Nick Diaz's memory. Why not send him a PM?

Kim

[earlfor]

The appropriate oil pressure depends on what type of main bearings your engine has. If it is a roller bearing engine, then you would have a high volume, low oil pressure system and the pressure would be 1.5 psi. If you have plain bearings, then you would have a high pressure, low volume oil system and your pressure should be between 40 and 70 psi. Increasing the oil pressure on a ball bearing engine would do no harm, but decreasing the pressure on a plain bearing engine from its required 40 to 70 psi down to 1 1/2 psi would be disasterous.
A plain bearing engine of any kind will not survive for long at high rpm and only 1.5 psi of oil pressure.

Earl

[saaz]

850s are roller cranks. factory specs for my Gs1000, which should be the same for most of them, specifys over 1.42 psi at 3000.

So as you see, high pressure is irrelevant, what they need it oil flow. Any car/plain bearing switch will never turn off the oil light.

Does the oil swith work ok in the normal setup without the oil cooler adaptor?

[jknappsax]

Oil Pressure sender in place of pressure switch?

My '78 GS 750 has a Lockhart oil cooler installed,with the adapter that goes in place of the old pressure switch plate to divert oil to the cooler, and a fitting for the oil pressure switch to thread into. I was wondering if anyone knew of an oil pressure sender that would fit that threaded housing, or an adapter that would allow a sender to be mounted there so I can run an oil pressure gauge?I would also like to run an oil temp gauge. Billp had mentioned in a previous post that he had a gauge where the sender mounted to the drain plug underneath the engine. Does the '78 GS 750 have the galley bolt mentioned on the 850 ( I have seen a bolt above and to the rear of the points cover on the right side of the engine at the base of the cylinders) , and if so, is this a possible sender mounting location?

[brs127s]

Okay folks,

I have done alot of research, and found out alot of info.

First I have to throw out a big thanks and sorry to Hap. I got your PM and read it before I read this thread. I just sent you a big reply(in PM form) which stated everything you had stated here, so sorry about that.

Okay...I have looked at some factory manuals and talked to several service folks at the motorcycle shop. Yes the 850 does have roller bearings. I know this, becuase I replaced the right hand crank seal, behind the ignition. Second, the 850 does have high volume, low pressure oil systems. The factory manuals for the 850 state the oil pressure to be above 1.4 psi and below 3.6 psi at 3000 rpm(it may have been 1.6 and 3.4) I will double check my notes later). The factory manuals for an 1100 state above 1.4 psi and below 7.1 psi at 3000 rpm. No one has the specs for the factory perssure switch. This still remains a mystery.

I don't know if all the GS's have it, but on the 850s, at the top of the crankcase, just below the back side of cylinder No. 4, there is a bolt which goes to the main oil gallery. This is where a mechanic would hook up a perssure guage, if they were checking the oil pressure.

Finally, the fiting for my new guage is M12X1.5. Although it is metric, 1/8X27NPT will screw into this fitting. It is tight, but it will work, and the threads will not be messed up.

Now, I have found a Borg-Warner pressure switch that is M12X1.5, and has a pressure range of .5 to 2 psi. I have not had a chance to try it yet. I am also going to try and find a low pressure guage, and will probably permanently mount it to the oil gallery plug on the right side of the engine. Once I get the guage hooked up, I will check the pressure with the orginal switch housing cover and switch. I will then place the adapter and new switch on and check the pressure again. If it remains the same, or drops a fraction, I will assume it is okay. The only time I am having a problem is when the bike is idling. The guy at the M/C shop I talked to said he probably would not worry about it. He figured if there was any drop, it was so small that it would not matter. Also we discussed, that the new switch could possibly have trapped air, and only gets enough pressure to shut the light off when revved up. I will do some testing on this also.

So far, that is all I know. Once I have tested some more, I will post my results.