Shimming oil pressure relief spring

[haggisbasher]

Evening all

The threads on my oil drain plug stripped at the weekend so I have dropped the pan to get a proper repair done. I have read some of the historical threads here that suggest shimming the oil pressure spring to improve oil pressure on this engine.

Since i have the pan off aanyway I would like to do this but info on the mod is fairly slim. Has anyone here done it and if so what did you use? The best thread I found quotes a NZ tech bulletin stating 2 x 6mm spring washers are the fix. What would you understand a spring washer to be?

Google says it could be this



or this



I'm leaning toward the second but looking for some guidance.

Thanks
Tom

[1980GS1000E]

My thinking is that they are talking about a washer that will hold against a spring. In other words, a properly fitting flat washer. That's what I would use.

[Steve]

Yep, simply a flat washer to add a litle bit of preload to the spring.

Sorry, but I don't have any dimensions available.

.

[GregT]

In NZ a spring washer is the second pic. I'd assume they were used because they were on hand and about the right thickness - and Suzuki NZ put out the bulletin because it worked.....

[rapidray]

In the USA, the first is a "wave" or spring washer, & the second is a LOCK washer. Ray.

[haggisbasher]

Thanks all

Greg It was your post I found glad your still around. I think I'll take some pics and put together a little how to for this mod to help my fellow mechanical illiterates.

Thanks again guys

Tom

[GregT]

In the USA, the first is a "wave" or spring washer, & the second is a LOCK washer. Ray.

Terminology differs Ray, your GS is my GSX....

[Guest]

Haggisbasher...can't wait to see your post with pics. This is one of the last few mods left to do on my '82 GS750EZ. Pretty much done everything else suggested here but like you, wanted to see some pics. Also be sure to add what size washer you use. Thanks

[subid]

Thanks all

Greg It was your post I found glad your still around. I think I'll take some pics and put together a little how to for this mod to help my fellow mechanical illiterates.

Thanks again guys

Tom

I would be interested in knowing how much this mod increases the oil pressure.

If possible, would you measure and let us know?

Stock should be above 43psi and below 78psi at 3000 rpm with a warm engine.

[haggisbasher]

I would be interested in knowing how much this mod increases the oil pressure.

If possible, would you measure and let us know?

I guess thats really the only way to determine the merit of this mod. The pan is already off awaiting me putting in an insert for the stripped drain plug. I dont have an oil pressure gauge but i will trawl around and see what i can find. If I can setup a suitable gauge in teh next couple of days i will button it up and do a before before stripping it down again and doing the mod and doing an after.

Anyone know the thread size on the oil pressure switch?

Tom

[Guest]

Any progress on thism mod? Anxiuosly waiting on pics as this is going to be a winter project for my '82 GS750EZ.

[Buffalo Bill]

I guess thats really the only way to determine the merit of this mod. The pan is already off awaiting me putting in an insert for the stripped drain plug. I dont have an oil pressure gauge but i will trawl around and see what i can find. If I can setup a suitable gauge in teh next couple of days i will button it up and do a before before stripping it down again and doing the mod and doing an after.

Anyone know the thread size on the oil pressure switch?

Tom

I would like to put an oil pressure gage on my GSX750F, but the gage I bought in the auto store uses ASE thread sizes, not metric.
I suppose the solution would be: IF the plug is wide enough, drill and tap a hole through it, to fit the oil gage fitting.

[Steve]

As I read these threads about shimming the oil pressure springs, I have to wonder: doesn't the spring just control the relief valve?

It is my impression (and I could be wrong here) that the oil pump will pump whatever it can, and it is constantly pumping against a spring-loaded relief system. If the pressure ever gets too high, it overcomes the spring and the pressure is reduced to acceptable levels. OK, shimming the spring will increase the pressure at which it will open, but I thought that the root desire for this mod was to increase the operating oil pressure, not the upper limit. Am I wrong?

From what I have read, to increase the operating pressure, you need to use a different set of gears (I don't remember specifics here) that have a different ratio, therefore they spin faster, or something like that.

I don't have one of the bikes that had this problem, nor have I had to work on one, so I don't have any first-hand experience, just trying to keep my facts straight so I don't go spreading any mis-information.

.

[haggisbasher]

I got the insert fitted in the drain plug and reinstalled the pan and exhaust on Sunday but the bike wont start. I also have to figure out a way to connect a pressure gauge in place of the pressure switch.

I put it back together stock so i can do the baseline as I dont think the info is very useful without a before pressure reading. Hopefully I can get it running and the gauge hooked up in the next week or so.

Tom

[Guest]

It was my understanding that Suzuki put out a supplemental memo to it's mechanics that this was an update solution to the problem of weak oiling for the top end of certain bikes. I forget which bikes and which years. Anybody have access to this memo and can share?