ramblin240

Car: 98 240sx w/ 02 LS1 T-56 installed by XAT (terrible) and fixed by Redstar Performance (amazing)

The issue I am listing here is one I came across the other day that I didn't have knowledge of beforehand:

Here is my issue: somewhere along the way the coolant line to my throttle body (passenger's side) was removed (not bypassed to driver's side like it should have been if done properly) and the coolant inlet (pass side) was capped with a rubber round cap.

The driver's side of the throttle body is still connected to the coolant air bleed line (like it should be stock) so to me it looks like half of the job of a throttle body coolant bypass has been done.

The cap burst the other day shooting coolant under my hood, and I have since replaced the cap and its holding. But, I need to figure out where the coolant supply line came from on the radiator and get it rerouted back to the tb so I can either put it back to stock or bypass.

What do yall think? The radiator is a koyo by the way.

Thanks for any help you can offer.

FastKat

iTrader: (10)

Can you post up a picture?

ramblin240

I dont have one right now, but its basically like this http://www.installuniversity.com/ins...e_tb_enter.jpg but there is no coolant line into the the tb and the cap looks like this http://www.installuniversity.com/ins..._enter_cap.jpg

There isn't a coolant line even present...

Stu Cool

iTrader: (13)

It needs to connect to the pressurized cooling system. You can either add a fitting to the radiator, or put a fitting in your radiator hose or a heater hose (Jagsthatrun has these fittings) or drill and tap to put a fitting in your water pump. If you do a search on coolant steam vent or coolant bypass you will find many threads on the subject.

Pat

FastKat

iTrader: (10)

Yea, it sounds like you have a line running from the block/head area steam vent to the throttle body, and it's just capped at the throttle body. That is not good. You need to run the line from the capped side of the throttle body, back into the cooling system.

The only problem is, I don't know for sure where you want to put it in the cooling system. This might help though:

http://www.midwayautosupply.com/pc-1...-34-47112.aspx

I think guys use fittings like this to plumb it back into the large coolant hose that goes to the radiator, but I am not 100% sure. A fitting like this might be a good start though.

ramblin240

I think i got it figured out, the GM radiator has two bungs on top under the radiator cap, one for overflow tank, the other for the tb, and the 240 radiator only has one...So i need to get another bung welded in...

FastKat

iTrader: (10)

You might be able to tee the one bung. It might not look as nice as two bungs, but it would probably get the job done just the same.

bczee

iTrader: (12)

Carefull... if the one bung is right under the Radiator cap, you shoud not use that one, It is open to the outside and recovery tank once the cap reaches it opening pressure. It need to be connected to the pressuse side.. many have made that mistake before.

Are you planning on keeping the TB inline of the head steam vent or going to bypass the TB ?.. either way, it need to be connected to the pressure side.

ramblin240

Crap..thats what I just got done doing...why cant it be connected that way? I just t-d into the line going to the overflow tank..

Stu Cool

iTrader: (13)

Because it is part of the pressurized system, if you connect it to the overflow, the pressurized system is vented and you cold end pumping your coolant into the overflow. Easiest solution is to put a connector like Fastkat linked to in one of your heater hoses and connect to that Chevy actually did that on some of their trucks and SUVs.

Pat

babydeuce

iTrader: (24)

Instead of messing with the radiator, do what was suggested above. Drill and tap the top of the water pump, and run the line to it. Alot of us conversion guys are running this setup with no issues. I run my 63 Chevy II this way, and have had zero cooling or leaking issues.

Jack

ramblin240

Where would you drill into? Any specific area?

ramblin240

Alright, Im gettin it welded today....

ccrider

iTrader: (9)

i'd also like to see where you guys are tapping into the waterpump

Stu Cool

iTrader: (13)

Here you go. I used a 1/8" NPT fitting. Use a Q size tap drill bit, .332 inches. Then use the 1/8" NPT tap. NPT gets wider as you thread it in, so don't try to put it in too tight or you risk cracking the pump housing. It is somewhat thin. Mine has been on there for 3 years now and almost 10 k miles without problem.

I have also seen someone drill and tap the front of the pump housing.

Pat

the_merv

iTrader: (88)

Some people run these LS Engines without that whole setup on them, they just cap it as the top of the Heads. These aren't like LT1's..the cool just like a SBC and I've seen them run without issues when that Head Venting setup(or whatever you want to call it) is removed.

ccrider

iTrader: (9)

thanks forthe pic stu.drilled and tapped this morning-very easy to do if anyone is thinking of doing it.

ramblin240

Got it welded yesterday and put back together...no DEX COOL...Prestone Green Stuff after full flush..

Runs great! Thanks for answering the questions and to miro for putting up with all of mine!

Pics

http://picasaweb.google.com/Andrew67...62171100875810

http://picasaweb.google.com/Andrew67...62176972263698

http://picasaweb.google.com/Andrew67...62183108671042

Stu Cool

iTrader: (13)

Glad you both got a solution that works for you. I forgot to mention for those who might drill and tap the water pump on the motor. To keep shavings from getting into the system I put grease on my drill bit and tap to capture the residue. I also had the shop vac sucking air out of the water pump outlet while I was drilling.

Pat