I was wondering if the top coolant nipple on the rear plate (the one that supplies coolant to the throttle body) can be removed and the hole tapped for a pipe plug? I was thinking about doing all my unused coolant and vacuum lines this way. I guess the nipples could be welded shut also... what do you think?

 

The Help! section in automotive stores has various sized caps (called 'Bypass Caps' on the packages) that can be used with a clamp to terminate hose ends. Not sure a more elaborate solution is required, unless you want to just clean up the engine bay.

 

If it's the rubber caps you're talking about, I would'nt use them for nothing more than capping vacuum lines. Don't believe they will hold up to pressure

 

i'd just weld them shut.

 

Yes, this is why I haven't bothered to use them...

 

i would really like to drill my water tubes out, tap and plug them. with the list of things to do before early april it isn't going to happen.

i would caution everyone against using (just) the cheap rubber caps. if one fails it is goodby motor.

i carefully filled the last inch of the water tube w good old silicone adhesive... the clear stuff. then i filled the cap w silicone and installed it w a clamp. i always use a turn or two of 3M electrical tape before installing the clamp so the clamp doesn't cut into the cap.

i ran my motor last year w 2 caps installed in such a manner and carefully inspected them recently and they are solid. not pretty but sometimes pretty is as pretty does.

howard coleman

 

They are coolant hose caps - not vacuum caps (at least the ones I have are - Help! also sell vacuum hose caps) so are designed for pressure.

The extra precautions listed by Howard probably would not hurt either.

 

Cant you just take the hose that goes to the TB and route it back into the block where th outler hose on the TB goes to and bypass it? Or are you just looking for a way to clean up the engine bay a bit?

 

I have been removing the nipples and tapping the holes for pipe plugs for 10 or 12 years with no failures . On the smaller alum parts I pull the nipples and have the holes wielded up before polishing .I also remove the factory plugs and have the holes welded for a cleaner look .

 

If you do this make sure you at least restrict it down to the size hole in the Thermal wax unit. other wise your just creating a bypass for coolant to route through the hose instead of the engine (if it's the path of least resistance). Some have done this (just hooked the hose from where it went to the TB to where the TB hooked back into the side housing and so far no one has reported any problems (at least none atributed to this by pass) just a heads up more than anything.

 

I ran caps on those coolant nipples for years without issue. There are some thin plastic looking caps from the auto parts store that hold up great, I put on of those on and then a coolant rated cap over it for a backup. With a good clamp these have lasted the test of time, heat, and lots of cycles.

 

For the coolant nipple on the top rear plate that feeds the TB - just drill it out 7/16" and tap it with a 1/4" NPT - straight and true. Use a steel plug with pipe dope ( teflon tape ) and you're done. Don't try to remove the nipple, just drill right down thru it and the iron. Use a magnet to pull up the filings.

On the aluminum nipples - pull and TIG weld up

On the side nipple that the heater return goes into on the rear iron - I am looking into a solution for it now. The hole is bigger than a 3/8" pipe plug and not enough meat for a 1/2" plug. Anyone welded this up ?

tom

 

I just ran a hose from the rear plate to the front inlet...I decided to keep the flow!

 

What was the reasoning behind this ? All your doing is providing flow through a hose when the flow could be better used through the motor rather than bypassing it. Remeber the hole in the thermal wax unit is smaller than the actual hose ID, and has to move different dirrections to get from one point to another. When you just run a hose (without restriction) it's a bypass and what it may be bypassing is a part of the motor.

 

Well the another determining factor was that I couldn't find a plug that was suitable....Well I also thought it coulnd't hurt either...So far I have had no problems with this. If anything I can use it to put a temp sensor there!

 

It doesnt make enough of a difference to overheat the motor. Ive been doing this on my FC for 4 years now and the FD for a while now. It really makes no difference. There is enough coolant in the system at all times to properly cool the engine and nobody knows for sure that the flow is less in engine than in the bypassed part. Its all speculation but as long as the motor doesnt overheat, which it wont, dont worry about it. My 2 cents.