One more thread on an oil cooler mod

[GregT]

Kyler, I applaud what you're trying to do but I have some experience of building sidecar motors and boy, there are pitfalls..

Firstly, the 750 plain bearing motors are an oiling problem by themselves...As I've posted several times the recommended fix for STREET motors here in NZ was to shim the relief valve with two 6mm spring washers...roughly equal to a 3mm shim. Mandatory in your application IMO.

Now sidecar race application...the oil pump pickup is the key. You've got to keep oil around it. Baffling of some kind WILL be required. Simple flat plate sealing off around the sump edges with a center hole for drainback can work as can the full swinging gates car style.Depends how serious you want to get.

i see what you're doing to fit a cooler and I think it will work. But doesn't anyone in your area TIG weld alloy ? The chairs have a well deserved reputation for oil leaks....try and avoid adding to this LOL...

 

[Kyler]

Kyler, I applaud what you're trying to do but I have some experience of building sidecar motors and boy, there are pitfalls..

Firstly, the 750 plain bearing motors are an oiling problem by themselves...As I've posted several times the recommended fix for STREET motors here in NZ was to shim the relief valve with two 6mm spring washers...roughly equal to a 3mm shim. Mandatory in your application IMO.

Now sidecar race application...the oil pump pickup is the key. You've got to keep oil around it. Baffling of some kind WILL be required. Simple flat plate sealing off around the sump edges with a center hole for drainback can work as can the full swinging gates car style.Depends how serious you want to get.

i see what you're doing to fit a cooler and I think it will work. But doesn't anyone in your area TIG weld alloy ? The chairs have a well deserved reputation for oil leaks....try and avoid adding to this LOL...

if you have some pics of the shim and where to shim I'd appreciate it! Same for the baffling. I'm stoked to get feedback from a fellow hack racer.

I TIG (poorly) and have access to a top notch guy when needed. I became quite proficient brazing chromoly doing repairs to my Wasp MX hack.

 

[GregT]

I'm not a sidecar racer !!! I consider myself sane...I've been turning down rides on those things since 1969....mainly I have to say, speedway sidecars though I've done motors for roadrace chairs too. i have a number of strange friends who race them....The only one I regret now not having a go on was a Black Lightning Vincent speedway outfit.
However - shimming the relief valve .i don't have pics but I'm pretty sure it's been covered here several times. Shim goes above the spring, under the circlip which holds the assembly together.

I've said it before here too but I've worked with these motors in speedway TQ's which were dry sumped. You could see 60lb pressure just above idle and stil have the thing do a big end. The air/oil cooled GSXR's are a generation better but that doesn't help you sorry.

 

[subid]

You might be interested in this oil cooler

http://www.ebay.com/itm/NOS-Suzuki-...8141&pt=Motorcycles_Parts_Accessories&vxp=mtr

 

[Kyler]

he wants way too much. You can get a 8-tube, double-pass Derale cooler from Summit for $60.

 

[Kyler]

Here's the final mod. I ended up having a custom filter plate made.

My new plate on the left and the stock plate on the right. The motor side shown.

My new plate on the left and the stock plate on the right. The exterior side shown.

Where it is going (after the filter is removed).

See? No filter.

New plate installed with -8 AN fillings. The #4 header needs to be rerouted to clear the fittings and (I hope) leave enough room for the Dzus fastern that holds the front of the drip pan.

Hoses attached. Not a lot of room is there?

That little can inline on the one hose is a manifold I made for the temperature probe. I wanted the oil temp coming from the motor versus after the cooler.

Here's the auto-style oil filter and oil cooler. The oil pressure sensor is on the outflow of the oil cooler so I know the pressure going back into the motor.

the wiring is a mess - still need to make a new loom.

 

[Kyler]

Shouldn't the bottom hole have an oring as well?
How do you get all the oil to go though without?

I am picturing an extra groove around the hole with a oring in it.

Daniel

Not necessary. The gasket actually compresses and seals it pretty good. If it does seep a little, that is okay. In the EFE motors there is actually a bypass there. I considered an o-ring but the time and expense to do that didn't seem worth it. 99.9% of the oil is going out the port where I want it.

 

[posplayr]

Not necessary. The gasket actually compresses and seals it pretty good. If it does seep a little, that is okay. In the EFE motors there is actually a bypass there. I considered an o-ring but the time and expense to do that didn't seem worth it. 99.9% of the oil is going out the port where I want it.

If I'm following correctly you are removing your stock filter and relying on the external one alone? If so any oil bypass at the cover will be unfiltered oil going back to the engine.

 

[Kyler]

If I'm following correctly you are removing your stock filter and relying on the external one alone? If so any oil bypass at the cover will be unfiltered oil.

true. Consider this. The gap there, if any, is incredibly small. Personally, I think it will be a tight seal. Also, I change the oil after every race weekend. If there is any bypass of "dirty" oil, it won't be very dirty AND if it has metal particles in it, I have a much, much bigger problem.

 

[posplayr]

true. Consider this. The gap there, if any, is incredibly small. Personally, I think it will be a tight seal. Also, I change the oil after every race weekend. If there is any bypass of "dirty" oil, it won't be very dirty AND if it has metal particles in it, I have a much, much bigger problem.

True, but the stock filter without the leak will filter better than your external with unfiltered bypass. On the other hand an o-ring is not perfect either so it is as you suggest about degree of bypass.

 

[Kyler]

final fit after header was rerouted. I had to add an extra 2.5-liters of oil. That gives this thing a huge oil capacity.

I started it and ran it for almost 20-minutes with a 20" fan blowing on the motor. I got 40# oil pressure at idle. Mild revs easily got the oil pressure up to 70-80#. I haven't downloaded the data for the guage yet so don't know how hot it got.

I'm off to Loudon this weekend to race. Will let you know what the data says after practices and 2 races.

 

[Kyler]

for those interested, we went to Loudon to race over the weekend. Three races and three practice sessions - cooler worked fine. The pyrometer showed 200 degrees on the cooler (the bars on the temp gauge are hard to read) after each session. Does anyone have hard facts on what the high end of the oil temperature should be? I'm wondering if maybe it isn't running a bit cool.

Oil pressure was a pretty constant 60-70# even pulling hard down the straight at 9K RPM.

Next on the list is to add a top-end oiler and I think I'll be fine.

 

[hotrods316]

is there any reason you went with this type of set-up vs. the one described on the flying bananna? (the oil cooler that comes out of the stock pressure sending unit?

PS- is there hack racing at the vintage days at mid-ohio? would love to check out this beast in person

 

[Kyler]

is there any reason you went with this type of set-up vs. the one described on the flying bananna? (the oil cooler that comes out of the stock pressure sending unit?

PS- is there hack racing at the vintage days at mid-ohio? would love to check out this beast in person

Yes, the vintage guys will be at Mid-O. I have a conflicting race or I would be there too. I'll be in NJ at the NJMP that weekend.

This motor does not have the oil galleries that he has. Plus, this motor is a 16-valve so the oil-pressure switch is in the oil filter cover. This mod is as close as you can get to what he did with this particular model motor.

So far it is working well. I have over 6 hours on it in race conditions with the RPM limiter set at 9K.

 

[Kyler]

I now have just shy of 9-hours on this mod in race conditions. It works well. The motor is putting out a solid 60# pressure at race speeds and 40# at idle. Temps have stayed in the 200-230 range (using a pyrometer on the oil cooler at the end of a race).

 

[GregT]

for those interested, we went to Loudon to race over the weekend. Three races and three practice sessions - cooler worked fine. The pyrometer showed 200 degrees on the cooler (the bars on the temp gauge are hard to read) after each session. Does anyone have hard facts on what the high end of the oil temperature should be? I'm wondering if maybe it isn't running a bit cool.

Oil pressure was a pretty constant 60-70# even pulling hard down the straight at 9K RPM.

Next on the list is to add a top-end oiler and I think I'll be fine.

I'm more used to seeing oil temp in deg C. 100C is too hot, most semi and full synthetics begin failure around 95C in my experience. 80 - 85 C is the range I'm happiest with. On that basis you may be a tad hot but you really need to measure the oil temp rather than the cooler temp..
Given short races and frequent changes you may get away with what you've got. A number of the top outfits here besides being water cooled, are on methanol which sidesteps the cooling issue totally.

 

[boingk]

200'F is about 90'C, and 230'F is 110'C.

Not bad range given the period of the engine and its use, I think.

- boingk

 

[Kyler]

thanks guys! Over the winter I'm installing a better oil temperature gauge that gives me a number versus a "band". Then I'll have hard data.