Cooler Add-on for 8 Valve engines using Oil Filter Cover

[posplayr]

WARNING

It appears as if there are some Oil Cooler installation on 8V motors that plumb the cooler between the back plate and filter cover. I?m pretty sure there will be an issue if you do this. I?m assuming that a fitting for the oil cooler is put into the center idiot light switch and another fitting is put into the center of the oil filter cover. The cooler in between.8-[


I did a little graphical analysis of three different oil flows. The first is the more common 8V oil cooler install. The second two have the oil filter cover plumbed in. I think the 2nd one is not possible and the third one is what happens when the oil filter cover is used. See the summary below. 8-[


The problem with using the filter cover as part of the cooler plumbing is that you have basically created a situation where the filter is not filtering all of the oil and any metal contamination that gets past the sump pickup and the oil pump can very easily go around the oil filter and do bad things.


I had to pick cam gear parts from my engine and replace the oil pump as it pulls from the sump and not through the filter (GS1100ED 16V). I am glad my motor was not configured like b.) (this flow is impossible) or c.) below. I also included the lubrication circuits to confirm that the analysis is correct.:shock:




http://www.posplayr.100megsfree3.com/gs750/ticking_bomb_8V_Filter_Cooler.pdf

Let me know if you disagree??

Posplayr

 

[robertob]

Yes. That's why my vintage Derale cooler has a metal matrix filter in the outlet line from the cooler.

 

[robertob]

... and by "outlet line" I mean the one in the filter housing. Since it's not sending all of the oil through it I'm not too worried.

Also, the cooler works well - oil temps on the "hot" side (connected to the filter housing) are 140 degrees after a hard run, and about 120 degrees F on the cold side.

 

[posplayr]

Sounds like you have it covered

Sounds like you have it covered

This slight subtlety could cause someone else problems though.

Was there are particular reason you went that route? Less expensive fittings?

TIA

Posplayr

 

[robertob]

It came with the bike - the whole kit was new in the box from 1978. It looked to be pretty good quality so I figured I couldn't go wrong. It works great.


That said, if I were to put one together I would just buy the Terry adapter and not worry about it.