How important is it to run coolant to a turbo (aftermarket)?

[MarkIII4Me]

I have a bolt-on 62-1 Turbonetics T4 (look at avatar) that has ports for both oil and coolant. The issue I have is, the previous owner of my engine never ran coolant to his turbo's and welded up the coolant outlet on the engine.

When I called him and asked if I could route the coolant from somewhere else, he told me not to even bother, leave the coolant port on the turbo open, and that he never runs coolant on any of his turbo's. His theory is that turbo's only house roughly 3 ounces of coolant and that coolant runs hotter than oil anyways. The guy races supra's all the time and even owns his own dyno shop, so I wasn't going to argue with him.

If I don't run coolant, will it harm the turbo and/or hinder performance. I figure if the turbo has a port for coolant, it was obviously designed to run coolant for a reason.

So what say you, am I better off just running no coolant at all? Otherwise, what's the best way for me to route coolant to the turbo now that the engine coolant outlet is welded shut?

 

[dumbo]

Coolant cooled FTW. Cuts your cool down time waaaay down. I don't know of any downsides, and coolant doesn't run hotter than oil. Please correct me anyone?

 

[IJ.]

The idea behind watercooled CHRA's is that it will thermosyphon after shutdown and keep taking heat out of the turbo.

In the old days this was a HUGE concern as the heat build up would cook the Oil and turn it to coke (Carbon) deposits on the shaft which is almost as hard as diamond and would trash the shaft and piston ring seal used in the hot end of the Turbo.

Turbo Timers were another part of the strategy to save Turbo's the idea being to wash the Oil through the Turbo before shutdown letting the shaft speed slow as much as possible.

Water cooling + Modern Oil formulations have helped reduce this coking problem, I have NEVER used a Turbo timer and just drive gently for the last minute or so before shutdown and have never lost a turbo.

Personally I wouldn't run one without water but if I did I'd be doing the Turbo Timer thing and run the very best Oil I could afford.

 

[Poodles]

Considering it also acts as a coolant bypass for the t-stat, I'd figure out some way to fix that...

Welding coolant holes shut is an idiot move IMHO...

 

[MarkIII4Me]

Considering it also acts as a coolant bypass for the t-stat, I'd figure out some way to fix that...

I'm all ears. Pulling the engine out and taking it apart is not an option. It just isn't. I'm sure I could probably drill it out while it's in the bay, but then I'm going to have metal shavings in the coolant passages. There is really nothing hooked up yet, not even a intercooler mounted. Could I just drill the passages out, flush water through the front of the engine to remove the shavings and then thread in a nozzle?

How would you go about it?

Welding coolant holes shut is an idiot move IMHO...

Agreed. I wish the guy would have just capped it off or something. This freakin engine has given me all sorts of grief already and I haven't even fired it up yet. And believe me, it was not cheap. I really wish I would have noticed the outlet being welded shut prior to installation

 

[Poodles]

Honestly dunno what to tell you... The top one would be easy as you could just replace the waterneck, but the lower one is part of the front case.

As you can see here, the N/A uses those ports for the water bypass, the turbo gets the coolant from these two ports as well (but the top one is on the top of the water neck and not the side). You MIGHT be able to do it on the car, but it's not going to be easy. Removing the waterpump would give you easy access to any shavings, it's just getting getting the hole straight and the face smooth that would be an issue if using the stock copper washers and banjo bolts. Might be easier with AN fittings, but that's not something I know about...

 

[MarkIII4Me]

I wouldn't dream of using the banjo bolt. AN fittings is probably the way to go. I'm not looking forward to drilling into my engine while it's in the car. I'm wondering if I shouldn't just leave it alone. What happens with the thermostat if it doesn't have this coolant bypass?

Is there some alternate area that's more easily assessable I can run coolant to the turbo from?

 

[funky_monkey58]

It it were me I would drill a hole for 1/4 npt tape it and use an an fitting. With npt the thread is tapered so you should not have an issue with sealing.

the top piece is 1/4npt factory anyway. Like as suggested if you remove the waterpump removing shavings will not be an issue just use a towel to deep them from dropping too far.

Hope that helps you out.

 

[Poodles]

You have full access to that area if you pull the waterpump...

Up to you...

 

[MarkIII4Me]

It it were me I would drill a hole for 1/4 npt tape it and use an an fitting.

What do you mean by "tape it"?


So what your saying is use an NPT/AN fitting with the NPT side screwed into the newly drilled outlet?

If I'm using an NPT fitting, do I still have to worry about making the area flat or can I just drill the hole and screw it in?

 

[Sawbladz]

What do you mean by "tape it"?


So what your saying is use an NPT/AN fitting with the NPT side screwed into the newly drilled outlet?

If I'm using an NPT fitting, do I still have to worry about making the area flat or can I just drill the hole and screw it in?

Pretty sure he means "tap". Meaning to put threads inside of an existing hole.

 

[MarkIII4Me]

Oh tap, yeah, I knew I was going to have to do that. When I saw "tape" it made me wonder if I was supposed to use plumbers tape or something; which of course would melt out of there as soon as the engine warmed up, so it didn't make sense to me.

 

[shaeff]

Drill, tap, and put in some -AN fittings.

 

[MarkIII4Me]

Ordered fitting, tap and drill bit.

It's in god's hands now .

 

[shaeff]

God works on your car?

 

[MarkIII4Me]

God works on your car?

Only on holidays; but he charges a premium.

 

[MarkIII4Me]

It it were me I would drill a hole for 1/4 npt tape it and use an an fitting. With npt the thread is tapered so you should not have an issue with sealing.

Well, that's not going to work :3d_frown:

I was checking out an extra cover I had and looking at the port, the 7/16 drill bit I was going to use for the 1/4 npt fitting is basically the same size as the coolant outlet. I went to my engine and stuck my finger in where the hose comes out and felt inside and around the back of where it was welded to see if it was welded all the way through. To my surprise, at least 2/3 of the thread is still there; maybe more. The previous owner must have just glopped the weld on the top of the port. If I drill it out for a 1/4 npt fitting, I will only be able to tap the 1/8" of weld and that won't be enough to seal.

The question is, should I just go a size bigger, drill out the old thread and still use a NPT fitting? Or should I just take a file and grind down to the original threads and use them? I;m not sure I can get the surface smooth enough though. I really do want to use NPT, but if I go bigger, I'm not sure if the walls will be too thin at that point.

 

[cmdeoro]

I know this is off topic but MarkIII4Me that is a sick as engine bay you have on your avator.

 

[MarkIII4Me]

Done! And the best part is that I didn't even have to remove the water pump. I took some adhesive putty and thinned it to around 1/8" in my hand. Then I fed it through the side opening where the hose goes and pushed it over the back of the water port hole with my fingers. When I drilled and tapped, the putty stretched back and collected all shavings; they just stuck right to it. I removed the shaving filled putty and replaced it with new putty between each drilling and tapping. It worked fantastic! No metal shavings anywhere inside.

To start, I drilled a guide hole with a dremel before drilling the hole for 1/4 npt with a 7/16 bit which actually was pretty easy. I had just enough room for the drill with the removal of the turbo.

I only had to drill in maybe 1/3 of an inch before I exposed the original threads.

I took a flat file and made the surface as smooth as I could without taking too much off. I wanted as many threads as possible. Then I went to a 9/16 bit to make room for the 3/8 tap. This is where I had problems. I guess I should have went 1/2" bit first since the 9/16 kept jamming and going all over the place. Made a real mess. Used plenty of lubricant, but it just wasn't helping. Luckily, I was able to keep the hole relatively straight. I used a wrench on the 3/8 NPT tap and it went in real smooth using plenty of lubricating oil. It threaded at sort of an upward angle, but it should be fine.

Then I put liquid teflon on the thread of the 3/8 npt fitting and used a 1/2 rachet with a 19mm socket to screw it in. I know a 1/2 is pretty big to use in aluminum, but it was all I had with a 19mm. Problem is, I was trying to get the fitting in as deep as possible since the 9/16 hole I drilled was a little wide at the beginning. I pushed my finger in behind the fitting to feel when it was close to the end of the threads. I may have torqued it a little too hard because about 1/8" away from the end of the threads I heard a faint "click" noise. I about shit my pants. I stopped right there. I didn't see any cracks on the housing and the back of the port felt smooth. I hope I just stripped a thread or too inside and not split the fitting or the housing. Hopefully all is well. The fitting is basically screwed all the way in and does not jiggle at all. So with the liquid teflon I hope there are no leaks. I guess I won't know until I fire her up.

Thanks for all the advice guys :icon_bigg

 

[MarkIII4Me]

F#ck me!!!

I cracked the housing :cry:

Not too bad tho. It's just a hair-line crack along the top, right where the fitting screws in. I figure I should remove the fitting, repair the crack, retap the threads to clean them out (maybe even go a little deeper this time) and screw in the fitting again.

What should I use for the repair? I don't want to just use something like JB Weld and then have it split when the aluminum heats up and expands. Can I use something like HTS2000 or similar weld with propane products?