Rebuilding LQ1 for Dummies: Oiling System!

[Mach10]

Here's my question thread continued

1) Oil Return: A large problem that I've heard of with this motor is the oil return system. Apparantly the pump throws too much at the top end and will actually drain the sump at high RPM. Anyone done anything to improve drainback? My machinist has actually suggested an external drainback system by plumbing a steel line through the cam carrier around the outside of the motor to provide another oil path to the sump. This would be accomplished by drilling and tapping a new passage through the head at a collection point, and shunting it off down through fittings and tubes appropriate for oil and high-temperature (read: SS tubing and hydraulic fittings)

Since some of the other "tweaks" involved restricting the flow of oil (which I don't really want to do) this seems to be a fairly simple and idiot-proof solution. Providing--of course--that it doesn't leak or punch through a water jacket This of course will be done in addition to removing any accesssible casting flash in the stock galleries.

2) That goddamn distributor plug. Anyone have any ideas on how to seal that bastard but good? I was thinking of having a cork gasket cut to seal under the flange of the plug to the block... In addition to that stupid o-ring. While I can see silicone-gasket material working... It's too ghetto for me to consider other than a temp fix (yep, I'd done that, too) Furthermore, I'd just LOVE to figure out how to make it accessible WITHOUT removing the head. Any thoughts?

3) Related to the oil question... Bearing in mind that I haven't yet seen the inside of this motor, is there any benefit expected from either adding a crank-scraper (I think that's what they are called... Windage tray that strips the oil off the crank at high-speed to reduce frothing and rotating mass) or modifying the existing tray to do a similar job?

4) How efficient is the existing oil cooler? Given the slightly heavier than normal duty that this motor with endure (enjoy? ) would it be worth-while to replace it with a more conventional Air-to-Oil rad-type cooler? How about a separate coolant system with a self-contained pump and small secondary radiator? I guess the question is: How hot does the oil get in this motor

[Kohburn]

distributor plug -- remove the hold down, pop the plug up with a screw driver and channel locks.. then use two screw drivers to stretch a distributor O-ring over the head onto the shaft.. bolt it back down - the oring will fill the gap and stop all leaks for as long as it remains supple

[Mach10]

Which for these motors is what... 2 months? I have YET to see a 3.4TDC (or pretty much any 60šv6) that wasn't at least damp with oil around the distributor/plug area

[Fierobsessed]

Well... I have a crate engine. Never used, never even turned. So I can tell you that contrary to what you might think, that the distributor plug does NOT leak from the factory

Actually, I think I just came up with a perminant solution... But I'll have to investigate it further. I'm a certified hydraulic mechanic (whooptie do) but I do have a lot of experience with leakage and there is a hydraulic seal type called a bonded seal, and slipping one of these bastards in, in addition to the O ring, might do the trick. However, on the DOHC, it still means the unit has to come out. It would raise the plug about 1/16" from its current seat. Perhaps a teflon seal backer, or maybe even a nitrile or buna seal would be better... Hmmm... things to think about while I'm at work.

[donk_316]

Nothing a quick zap with a Tig wont fix!


But on topic, the only fix i have come up with is increasing the pan volume and a proper oil cooler.

[Mach10]

Might be tricky welding aluminum to cast iron...

Pan volume will be a bit tricky given the limited market of pans that will fit on our cradles... 'Specially since I'll be using the dodge truck mount mod to lower the engine and trans a little (decklid clearance issues).

I rather like the idea of auxilliary oil drainbacks, but I will freely admit that it will be much easier to envision once I have the cradle back out (and once I tidy up all my wire looms and hoses etc).

[donk_316]

There is alot of room to expand the pan either back or forth.

We are talking fiero cradle right?

I dont know anything about the family car cradles.

[Mach10]

GM makes other cars?!?

[series8217]

Re: Rebuilding LQ1 for Dummies: Oiling System!

Here's my question thread continued

1) Oil Return: A large problem that I've heard of with this motor is the oil return system. Apparantly the pump throws too much at the top end and will actually drain the sump at high RPM. Anyone done anything to improve drainback? My machinist has actually suggested an external drainback system by plumbing a steel line through the cam carrier around the outside of the motor to provide another oil path to the sump. This would be accomplished by drilling and tapping a new passage through the head at a collection point, and shunting it off down through fittings and tubes appropriate for oil and high-temperature (read: SS tubing and hydraulic fittings)

Since some of the other "tweaks" involved restricting the flow of oil (which I don't really want to do) this seems to be a fairly simple and idiot-proof solution. Providing--of course--that it doesn't leak or punch through a water jacket This of course will be done in addition to removing any accesssible casting flash in the stock galleries.

All excellent ideas. I spent two hours deburring my block and cleaning every casting line off the interior of the cam carriers and block. The worst area is right near the timing chain; the casting flash reduces the drainback area to half the side it should be! Also pay close attention to the deck surface; the holes coming out of the top of the block do NOT match the drainback holes coming off the head; there's a huge step in the way. Set a head gasket on there and you'll see where the step is. Ouch! GRind grind grind away.
The cam carriers are also a very bad spot. They are cast in top and bottom halves and there is generally a huge step between them and massive flash in all the drainback holes. Grind away!
After you're all done, make damn sure there isn't a spec of metal grinding chunks left anywhere inside your cam carriers, heads, or block. The carriers are really hard to clean out, you need some very good brushes, an air compressor, and a jet wash.
For the block, you're going to have to drill out the rivets holding the baffle into the block as you have to grind the top side of the hole it protects from windage. Metal bits WILL collect behind it.
Replace the baffle by drilling and tapping the block for some small machine screws. Spray out the holes with brake cleaner and make sure there's not a spec of oil so you can get some red loctite on the bolts to make them stick.. wouldn't be too nice to have that baffle come out and get jammed into something.
The external drain is surely to help; there are drainback passages on the head that have 1/4" or less between them and the outside of the head; a perfect place to add something to collect any flow backup... though if the passages are all ported it may not be necessary.

3) Related to the oil question... Bearing in mind that I haven't yet seen the inside of this motor, is there any benefit expected from either adding a crank-scraper (I think that's what they are called... Windage tray that strips the oil off the crank at high-speed to reduce frothing and rotating mass) or modifying the existing tray to do a similar job?

It can't hurt but there is already a regular windage tray.

4) How efficient is the existing oil cooler? Given the slightly heavier than normal duty that this motor with endure (enjoy? ) would it be worth-while to replace it with a more conventional Air-to-Oil rad-type cooler? How about a separate coolant system with a self-contained pump and small secondary radiator? I guess the question is: How hot does the oil get in this motor

The factory oil to water cooler is great! Not only will it keep your oil and water temperatures close together (and thus the oil cool) it also heats up your oil faster on a cold start.

Well... I have a crate engine. Never used, never even turned. So I can tell you that contrary to what you might think, that the distributor plug does NOT leak from the factory

Actually, I think I just came up with a perminant solution... But I'll have to investigate it further. I'm a certified hydraulic mechanic (whooptie do) but I do have a lot of experience with leakage and there is a hydraulic seal type called a bonded seal, and slipping one of these bastards in, in addition to the O ring, might do the trick. However, on the DOHC, it still means the unit has to come out. It would raise the plug about 1/16" from its current seat. Perhaps a teflon seal backer, or maybe even a nitrile or buna seal would be better... Hmmm... things to think about while I'm at work.

I'm not even using an O-ring on mine, just a siliconed Chevy V8 distributor gasket. It works great!

If you have any other questions let me know. I have a 93 3.4 DOHC in my 88 Fiero coupe. I rebuilt the motor over the summer. You're welcome to call me on the phone if you have any questions about the motor assembly; there's quite a few tricky things to deal with when putting together this motor.. just send me a PM and I can give you my number.

[Mach10]

Series:

Thanks... Aren't you also on the RFT board?

The whole block is going to be tanked, deburred, squared, then tanked again. Not too worried about metal flakes, as I will be more than careful

I think I'm going to install the drainbacks anyway, on the assumption that if it was a problem before, better oil flow can't possibly hurt the motor

As for the windage tray, I mis-spoke. I was thinking crank scraper I noticed a crank-scraper available on the site, it's being taken into consideration.

[OldSkoolGP]

One issue I addressed on my motor was the bypass on the oil filter. When your oil is cold or the pressure becomes too great, the bypass opens and lets oil back into the motor before it's filtered. The fix was simple, I just drove an aluminum dowel into into the bypass to plug it. So far I haven't blown an oil filter up or even had one leak, and I'm much happier knowing that my oil is always filtered.

[Mach10]

The car isn't going to be driven in the winter anymore, and I'm pretty anal about oil-changes. I'm not terribly concerned about the filter bypass accidentally opening up.

I never drive a car straight off the line anyway, I usually let it "warm up" for at least a minute. At the very least, I have a half-mile long gravel road off my driveway to the main road that I don't (can't) go down much faster than idle 'cos it's a fncking washboard

Hmm... Actually, maybe I should consider it, since oil pressure could become an issue at high RPM.... Especially with no restrictions to the top end to "control" oil pressure as the pan drains

[series8217]

Series:

Thanks... Aren't you also on the RFT board?

Yeah, I was gonna tell you to join up but I recognized your name so I figured you were too. I imagine you've seen my threads then, and my buildup on PFF?

The only thing I don't like about adding the external drainback if you don't need it is that you're adding new places for oil leaks and possibly massive losses of oil if the fittings come loose.

-Steven

[Mach10]

I love wiring in gadgets... I could always wire in an "Oil Low" sensor from a 96+ motor and hook up an indicator lamp for it.


In any case, I've got a oil press and temp guage perched right by my tach... I'm a nutjob about keeping an eye on all three

In any case, if I bend myself some decent steel lines, tap the holes properly, and use good quality fittings, they should seal better than the rest of the block


I don't hang out on RFT that much, mostly 'cos I hate having to wade through Arronns crap posts every time I ask a question. That one brings out the worst in me