Trying to restore the TB coolant flow

[Don in VT]

Hi All,

I am trying to restore the TB cooling flow. At this time I have a long hose that connects to the hard fitting on the drivers side and goes under the intake bellows and connects to the coolant hard line on the passengers side thus bypassing the TB. I want to bring the TB into the coolant flow. This looks like a no brainer but I have run into a problem. Just for the fun of it I connected a hose to the Plenum fitting and tried to blow through it to see if it was capable of passing coolant and the pass through is blocked solid. Obviously if I hooked up the coolant lines there would be no flow. My question is, when someone want to take the TB out of the flow path do they do something on the TB internal flow path to block it or do I have a problem on the inside of the plenum or TB ?

Any thoughts on this would be appreciated.





Thanks,

Don


:flag:

[scottfab]

Hi All,

I am trying to restore the TB cooling flow. At this time I have a long hose that connects to the hard fitting on the drivers side and goes under the intake bellows and connects to the coolant hard line on the passengers side thus bypassing the TB. I want to bring the TB into the coolant flow. This looks like a no brainer but I have run into a problem. Just for the fun of it I connected a hose to the Plenum fitting and tried to blow through it to see if it was capable of passing coolant and the pass through is blocked solid. Obviously if I hooked up the coolant lines there would be no flow. My question is, when someone want to take the TB out of the flow path do they do something on the TB internal flow path to block it or do I have a problem on the inside of the plenum or TB ?

Any thoughts on this would be appreciated.





Thanks,

Don


:flag:

Don,
Pull the top plate off the TB and inspect. It's hard to say what someone did to it. That's the problem with the various "improvements" made. If they are not documented, how good are they really?

[Don in VT]

Great point Scott. This will be easy as the whole TB has been dry for a long time.

Thanks again to to you and Dynomite for the replys.

Cheers,

Don

:cheers:

[Corbusa]

man i wish I could copy those pages on the link.. Great , helpful info

[Don in VT]

An Update !!

I pulled the TB coolant chamber cover expecting to see it plugged solid but it was clean as a whistle. I air hosed the inlet and outlet pipes and the TB coolant passages and some accumulated stuff was cleared. After looking at the situation I discovered that the drivers side inlet pipe and TB passage was now open up but restricted when compared the the passengers side coolant pipe. I have looked everywhere but I cant find any reference to the coolant flow in the TB.

Does anyone have any experience with the TB and the coolant flow ? Is there a "built in" restriction in the drivers side TB passages or should they both flow the same ?

Thanks,

Don

[Ronstar]

Dumb question..but why do guys eliminate this?

[scottfab]

Dumb question..but why do guys eliminate this?

I am going to keep your entire quote. Modifying it could lead to confusion.

There the is a few minutes saved when removing the plenum.
I don't think it's worth the risk.
I leave it unaltered because it was designed in so that ice does
not form in the plenum. Ice formation was responsible for damage to some proto type LT5s during development.
It is a rare event but I personally never want to have to worry about it.

[Don in VT]

Hi Again,

With all due respect to the folks that want to bypass the TB and or the Plenum coolant flow, I totally agree with Scott and my TB is now in the coolant flow again. I must admit that the upper engine plumbing is messy and can be troublesome for small coolant leaks but after I dodged a bullet on a air locked WP I will deal with the coolant when pulling the Plenum and keep the entire cooling system stock.

FWIW, On my old 87 L98 I did the Plenum bypass trick and because my 87 was a daily driver, winter and summer, I did, in fact, ice up on one occasion. Not the end of the world but it ran like crap. Took off the bypass and all was OK.

Thanks everyone for weighing in on this issue.

Cheers,

Don

:salute:

[Jim Nolan]

Good luck finding a gasket for it. I had to make my own with some gasket material. It was one of the toughest leaks for me to stop.

[Don in VT]

Hi Jim,

Thanks for the heads up on the gasket thing. Regarding gaskets, Jerrys Gaskets has the the correct gasket for this fix and he can probably provide you with most of the ZR1 gaskets that you might need. Jerry has great service and the prices are very fair.

I was fortunate enough to have a new gasket and so my issue is solved.

Have a nice weekend,

Cheers,

Don

:proud:

[Jim Nolan]

I know about Jerry's and have purchased from him. When I needed it years ago he wasn't in business.

[Hog]

I leave it unaltered because it was designed in so that ice does
not form in the plenum. Ice formation was responsible for damage to some proto type LT5s during development.
.
Did the damage have anything to do with a prototype LT5 being stuck at WOT due to a stuck t-body blade? I wonder if the prototype ECM calibrations were rev limited?

Icing t-bodies are a horrible feeling, gotta get to the ignition quick and shut er down.

These types of mods are popular because they CAN be done by the layman, not much heat would be transferred into oncomming air from the t-body at WOT.

peace
Hog

[scottfab]

Did the damage have anything to do with a prototype LT5 being stuck at WOT due to a stuck t-body blade? I wonder if the prototype ECM calibrations were rev limited?

Icing t-bodies are a horrible feeling, gotta get to the ignition quick and shut er down.

These types of mods are popular because they CAN be done by the layman, not much heat would be transferred into oncomming air from the t-body at WOT.

peace
Hog

No recollection of any stuck blades or over rev. As I recall there was ingestion of ice that broke loose. Maybe JVD remembers. It's all in the email archives of the old list.

[Z51JEFF]

Dumb question..but why do guys eliminate this?

I bypassed mine to keep the TB paint form getting damaged.Im in Ca,cars stays in the garage so Im not worried about it.

[scottfab]

I bypassed mine to keep the TB paint form getting damaged.Im in Ca,cars stays in the garage so Im not worried about it.

I keep my TB top plate well sealed. No paint damage. And I never worry about icing. My TB coolant hose is in place.

[Paul Workman]

Dumb question..but why do guys eliminate this?

My reasons...

1) Much "stuff" is under the plenum. Without having to fuss with draining coolant and refilling it (and getting the air out of the system), bypassing or (as I did) plugging the passages off entirely elimiates both PIA parts associated with coolant draining. (With air ratchet in hand, I can have the friggin plenum off in about 5 minutes (leave the throttle lines connected), and on again in a few more (depending on condition of the gaskets). Fussing with coolant can easily add an hour to that process, has been my experience.)

2) The plenum runs significantly cooler (tho I too question the idea of much heat actually being transferred to the air at WOT), and the corrosion issue (even with new gaskets!) bit me a couple times. But, cooler is better for performance, and every little bit helps. (Lingenfelter provides some thick insulating gaskets to isolate the plenum from engine heat, FWIW.) Marc Haibeck told me he has run his in the Chicago area for years and in sub freezing temperatures w/o any problem with icing. Same goes for me, tho I admit I don't drive it more than a few minutes in winter and never on foggy days either! I'm not at all worried about it.

To scottfab: For a liberal, you're awfully conservative about making changes - at least as far as the LT5 goes!! :razz:;)

P.

[scottfab]

....snip....
To scottfab: For a liberal, you're awfully conservative about making changes - at least as far as the LT5 goes!! :razz:;)

P.

I'm fairly neutral when it comes to the the bypass. I think there's plenty of evidence to show icing is an extremely rare event. I choose to error on the side of caution mostly because the climate I'm in. So with me it is a "thought through" decision. That's the difference between an ultra conservative and a moderate like me. I get what facts I can and decide. If you continue doing progressive things like thinking and weighing pros and cons before you decide things you're going to loose your membership as a card carrying conservative. Next thing you know you'll be labeled a radical :nono: =D>
Here is an interesting site for measuring yourself against know liberal and conservative morals. You can find out where you "really" are not where you "think" you are. The down side is it take a commitment of time to find out.
http://YourMorals.Org

[scottfab]

Is the political part of your discussion On Topic ;)

I can see how YOU would see this as political. I think you should be making your "funny" attack on Paul. I was just responding. I don't particularly see this as political. It's more of an approach to problem solving and the "handles" put on the approach to decision making. There is no mention of candidate or political party therefore no politics...... it's only YOU fanning the blaze by using the word "political" see my funny faces :):):)

You kind of backed of TB icing saying icing is an extremely rare event especially in my view that the TB coolant system is essentially an air bleed system vice a TB heating system ;)

Did you mean "of" that makes no sense.
I bet your meant "off". I would have posted that in a PM but I'll keep with your style of making such things public.

The rest of your statement makes no sense to me. But then it is "your view" so I guess that's fine. Based on the facts I have, the plenum coolant system was added to avoid icing NOT as an air bleed system but you can call it "your" air bleed system.

And then only if you have difficulty refilling your coolant system after opening it up for leak repair or Plenum/IH Housing, Head removal or Water Pump repair.

Very incomplete list of "opening it up for ....."
You forgot starter, coils, wires, injectors, etc, etc and also:dancing etc.

[Z51JEFF]

I keep my TB top plate well sealed. No paint damage. And I never worry about icing. My TB coolant hose is in place.

Ive found the coolant saturates the gasket and at some point can migrate towards the painted area of the TB plate.

[scottfab]

Ive found the coolant saturates the gasket and at some point can migrate towards the painted area of the TB plate.

Yah, I've heard of that happening. I solved that by using rubber gaskets on both the plenum and TB cover. That was over 10yrs ago. No runs, no drips, no errors since. The side benefits are you don't have to pay for new gaskets because they don't stick, rip apart nor allow coolant to migrate toward the paint.

[vilant]

Yah, I've heard of that happening. I solved that by using rubber gaskets on both the plenum and TB cover. That was over 10yrs ago. No runs, no drips, no errors since. The side benefits are you don't have to pay for new gaskets because they don't stick, rip apart nor allow coolant to migrate toward the paint.
Scott, where did you get the rubber gaskets from? Did you buy them complete or did you buy a sheet of rubber and make your own? :cheers:

[scottfab]

Scott, where did you get the rubber gaskets from? Did you buy them complete or did you buy a sheet of rubber and make your own? :cheers:

Well, I did cut them myself but I made a template (the OP may recognize the material I used for the template)
The template is not really necessary. You can just put the plenum down on the rubber sheet (1/8 - 1/4 thick) and trace around it with a ballpoint pen, then cut it out. I took the extra time to cut the template because I thought I'd be cutting more of them. (nope, not so far)
Rubber is the ideal material. It makes a great seal, does not stick and very heat tolerant a the temps on the plenum.
http://zr1.net/forum/picture.php?albumid=199&pictureid=1465

[vilant]

Well, I did cut them myself but I made a template (the OP may recognize the material I used for the template)
The template is not really necessary. You can just put the plenum down on the rubber sheet (1/8 - 1/4 thick) and trace around it with a ballpoint pen, then cut it out. I took the extra time to cut the template because I thought I'd be cutting more of them. (nope, not so far)
Rubber is the ideal material. It makes a great seal, does not stick and very heat tolerant a the temps on the plenum.

Good thinking. Thanks.:cheers: