Ramo7769

Hi all, I am in the midst of an oil cooler install on my 1999 FRC. I have seen lots of DIY notes on oil cooler installs, but it doesn't seem that many pre-fill. Looking at a generic oil circuit diagram (http://i172.photobucket.com/albums/w...OilCircuit.jpg), that doesn't look like a good idea to me. With the lines and the cooler, it looks like a lot of air would flow through the cam, crank journals, pushrods before any oil showed up.

I'm a little uneasy about it and was considering just doing a dry crank before running the engine. I haven't found how to do this, but I think the easiest way may be to pull the fuel pump fuse. I'm looking into it now. Just wondering if anyone else has gone through this and has some insight.

Thanks

ZedO6

Just pull the fuel pump fuse and crank on for 15 secs, off for 10 (so you don't cook the starter) and repeat until the system is filled. You can crack the return line to check. If you don't run a bypass or T stat, you should be able to watch the OP gauge to know when its full. I would never fire it up without doing this.

Supercharged111

I yanked the plugs that power the coils before firing mine. Takes a lot of cranking to fill that cooler, believe me!

Ramo7769

Thanks for the input, guys.

I've pulled the fuel pump relay (#35 in the under hood fuse box for reference). Just finishing mounting the cooler and will pre-fill and then run it. Pulling the plugs sounds like a good idea too since she might want to run briefly with residual fuel in the lines.

ZedO6

Won't run without fuel pressure, won't even pop IME. But pulling the plugs will make the engine spin easier.

Ramo7769

Zed06 was right. Didn't fire without fuel pressure. Live and learn. Pressures looked good once I started it too. Still around 40 psi after a cold start with 5w-30. I ran the car on the track over the weekend and saw oil temps stay below 250F.

The only concern I have now is that it seems the oil pressure builds slowly at each start up. Is this just the way it goes having added such a detour and resistance to the oiling circuit? I also might just be a little over sensitive to it.

ZedO6

In my experience anytime you add that much plumbing to the oil circuit you are going to see the oil pressure build more slowly on cold fire up. The solution for me was a fuel pump toggle switch that allows you to crank the engine until you see oil pressure and then hit the fuel pump "on" which will fire the engine normally. Also convenient after an oil change or any time the car has sat for a while.

Depends how **** you are about oil pressure on start up.

Ramo7769

Nice to hear from someone as **** as I am about it but with more practical experience! Do you delay start every time or only cold starts, oil changes etc.? Even with hot starts at the track, I find myself cringing a bit as I see the needle slowly move 5, 10, 15, 20, 30 psi after start up.

hklvette

Even with low oil pressure, as long as the engine isn't loaded you should still be okay. I say this because large diesels can go for quite a while without any pressure at start-up, and doesn't cause any ill effects long term. If anything, they would be more susceptible to bearing damage due to their higher static compression ratios.

my $.02

btw, YGPM.

Rx7Rob

Nice solution. Where did you splice in the switch? How long do you typically crank prior to a cold start?

ZedO6

My track cars always seem to sit for a long time between engine starts. Why subject bearings to metal to metal contact if it can be avoided?

I spliced the switch wires into the fuse box from the back. I cut, soldered and shrink wrapped the connection and then ran it into the passenger compartment through an existing opening and hid the switch.

Rx7Rob

Got it,

rithsleeper

Couple questions: 1. You say cranking without firing is a good way to get oil pressure so wont run on dry bearings, but to me does it really matter if it's turning by the starter or under power? It would seem you are still turing it dry right? pulling a distributor and spinning with a drill would be the only option.

2. If the oil cooler feed/return lines are mounted sideways or on the bottom, will all the oil drain out and you would always have this huge vacant oil space to fill every single fire up? If not how do you get the oil out to change the oil?

Im getting ready to mount my cooler I just got....

fmcokc

Guys,

Just hold your foot to the floor on the accelerator and crank. Most EFI systems are designed to allow for cranking under this scenario without starting. I haven't tried this on the C5 but have on many other vehicles and it works great. One thing though is to see oil pressure it would be best to pop out those spark plugs.

hklvette

This. Its in there to help clear a flooded engine just like you would clear a flooded carbureted engine.

froggy47

I believe the needle and or the digital (HUD) gauges have some lag in them, nevertheless, lot's of good ideas here. I don't worry about it & my Blackstone is aces.

SouthernSon

As I have stated here before, small aircraft engine manufacturers state that one should shut the engine down after initial starting if the oil pressure doesn't build after 30 seconds. I had a bad (warped) crank from an 0-200 engine that I purchased years ago and found it would take quite a few seconds to build pressure. Finally, after several times of not seeing oil pressure within the 30 second window, I tore the engine down and found the warped crank ( probably a prop strike that the previous owner forgot to mention). All of the bearings looked good except the ones toward the middle of the crank where they were worn from the warped crank. I no longer sweat the oil pressure at initial start up.

sperkins

I stopped worrying about all that after I tore down an LS6 after it had been sitting on the engine stand for well over a year.
There were oil droplets still hanging from the cam and crank lobes.