seriously tho, i would weld it... before i pulled it apart again

 

That's the worst part! It drives great
What would a welder do? weld my iron center plate to my aluminum housing? ....All the way around? This does not seem like a good idea. In addition to possible warpage, it could potentially melt the seals and make the problem worse.

HUGE is an understatement. After punch a few bricks to dust I have decided to follow the procedure in thus thread https://www.rx7club.com/1st-gen-archive-71/engine-coolant-seal-repair-maybe-750774/ and use some AlumAseal to try to fix this problem.

Since the leak involves the pressure of the cooling system forcing coolant out, this product should work pretty well. There doesn't seem to be any coolant getting into the combustion chamber (no steam/smoke) so This leads me to believe the inner seals are ok, but even if they weren't the alumaseal would be sucked into those cracks as well. There are no signs that combustion gases are getting into the coolant, which is good because that's the one type of leak this product does not seem to seal well....

 

so you think the outter coolant seal is failing? I've never seen that. and i've reused the outter blacks ones over and over again,.. still none failing..

in the pix it looks like it's just a hole in the housing, that why i would weld it, if it's a metal whole.. if it is the seal then yes... rebuild time.

 

Its definitely not a hole. coolant is weeping from between the housing and the iron. It slowly pools up until its enough for a drop and then it runs down the seam and onto the ground. What kind of crazy bullshit is this?!

Update:
I put one tube of AlumAseal in the lower rad hose, blocked off the coolant feed/return to the turbo and ran it for 20 min or so, no die. The low coolant buzzer went off and shortly after it cut off and wouldn't re-start w/o pulling the egi fuse. Still no exhaust smell in the coolant or smoke/steam from the exhaust.

I may get a bottle of the liquid alumaseal and pour some in before I crank it up again

 

Put in about half a bottle of the AlumAseal liquid last night, ran for about 15-20 min before it started getting hot due to air in the coolant system. It was dark so I couldn't check for leaks.

This morning I stared it up and it cranked right up and ran fine for 15 min until it got up to temp, then the high idle (1700 rpm) gradually fell about 10 rpm / second until it stalled. It would not restart even after pulling the egi fuse.

A few hours later I went back and after pulling the egi fuse I was able to get it to turn over, but it died, even while feathering the throttle

 

Try disconnecting the battery to reset the ecu. That's probably whats keeping it from starting.

And a side question, you used an s4 NA block with s4 TII outer components. Wouldn't afr's be different between NA and TII although using a TII ecu since compression is higher in the NA block? Is a tune required for this?

 

Noobs . The ecu has nothing to do with it not starting. The fact that the combustion chamber is full of coolant on the other hand....

The fueling requirements aren't that drastically different out of boost on a stock port engine (especially since the stock ecu runs fairly rich to begin with). The biggest difference is the timing and that is why if you want a 6p-t to last you need some method of timing control. I have an rtek 2.1 which gives me that capability.

 

I have decided that a more drastic fix is required, and will be attempting the block weld trick located here: http://www.rotaryresurrection.com/3r..._seal_fix.html

I drained and flushed the system, filled it with purple power and water, and have cycled clean water through about 4 times so far.

I drive around the neighborhood for about 5 min before the low coolant buzzer comes on and temps creep up to 200* I then pull into the driveway, and find that the 1.5 gal jug I'm temporarily using for a coolant overflow tank is almost full.

I then drain the container, pop the lever on my rad cap (actually the AST cap) and wait about 5 minutes while the steam in the system bleeds off.

I then remove the cap completely, fill the system with fresh water and take it for another couple laps.



Here's the problem:
How the hell am I supposed to let it idle for 20-30 min (not driving) when I can only drive the damn thing 5-10 min before it starts trying to get hot?

 

So after another 4-5 rinse cycles, I'm pretty confident the remaining particles of AlumAseal shouldn't hinder the blockweld process. However I'm still left w/ the slight issue of the car attempting to overheat if left on past 10-15 min. So I've devised a multi-part strategy to try to work around this issue:

1) The writeup specifies "block weld" or some other granular based (water pump damaging) sealant. This is convenient because you can put it in cold, and then get the engine up to temp, the pellets will melt once hot enough....

I can't afford to wait that long, so I found some liquid glass type sealant that looks like a copper milk shake and is added to an already "hot" engine.

2) Regardless of the sealant, they recommend running the engine for 20-30 min. This gives the sealant enough time to find the numerous places where the coolant seals aren't doing their job....

Problem here is that I don't have that long (unless the stuff works so fast that it keeps all the coolant from puking into the overflow tank in 5-7 min?). I bought twice what it takes to treat the FC cooling system in hopes of doing 2 treatments:

Stop-gap treatment, run as long as it will stay cool, then shut it down. The theory being that the extra pressure in the cooling system will quickly find the external leaks, then once the car is allowed to cool, the coolant attempting to sneak into the combustion chamber will draw the sealant in with it. Not a lot (as most will probably be puked into the overflow) but just enough so that when i apply the.....

Actually treatment, the leaks will have been sufficiently slowed to allow the full 20-30 min run time and thus be properly sealed.

 

A lisle funnel should allow air/pressure to escape but keep the water and sealant mixture in the block. It'll disable the overflow system if it's all stock or you can just route any other overflow tubes back into the funnel.

 

just trying to help
either way, good luck.

 

About that....its a v-mount so I'm not sure that would work, it seems to rely on the pressure of the cooling system to force coolant back into the rad. I go drive for 5-10 min and the low buzzer goes off, the overflow is full of bubbling coolant and the rad is full of steam, the top tank is barely even hot. The AST on the other hand is scalding

Sorry, didn't mean to give you a hard time, I'm just pissed about this pieceofshit engine that was sold as good.

 

^Isn't that the water pump and thermostat's job to circulate coolant to the rad? The lisle funnel at the water pump outlet should at least allow you to keep adding water to the sytem even if it dilutes the sealant mixture a bit. Sorry, if this isn't helpful, but I saw your old engine bay pic and still have no idea how it's set up to function and include an AST. It's just a giant picture of an intercooler.


I'm curious where you're getting your baseline NA-t timing maps, but first things first.

 

You would think so wouldn't you? But apparently that is not the case.

My system uses the rotary works ast/ wp outlet. The outlet connects to a 180* hose that connects to the rad (modified koyo) inlet. The rad outlet connects to the wp inlet via a long (2-3') flex hose. For more details on the v-mount setup see the original thread:

https://www.rx7club.com/2nd-generation-non-technical-pictures-198/want-v-mount-dont-want-give-up-anything-%5E-ktec-%5E-933572/

I rigged up a funnel system to try what you suggested, but it just filled up the funnel and the low coolant buzzer went off after about 3 minutes so adding water via the funnel is not really an option since it would just make it fill up faster and it doesn't seem to circulate back to the rad.

 

Hah! Nice setup. So I basically told you to install a ghetto rigged AST on top of your real AST.
Is there any fluid coming out of the radiator overflow tube to indicate there is fluid pressure in the rad? Any blockage in the rad or hoses, like a rag from a disgruntled shop mechanic?

If not, it sounds like the combustion gases are getting into the coolant system faster than it can bleed off the air by itself. I'm not going to say the "R"-word, but....yeah.

 

Yeah...lol, but it seemed to be helpful ....for a little while. Eventually it just fills up and overflows, and the rad is drained of coolant.

There is no blockage, I fill the AST to get coolant into the rad, and the weight of the water is enough to force it through the 180* hose and into the rad. Which is odd considering it refuses to do so while running.

I tried every possible combination of non-venting caps and vent locations to try and force coolant into the rad. The most effective was using a leaking(on purpose) cap on the rad, w/ the rad nipple vented to a bottle and a sealing cap on the AST. This forced coolant into the rad, and for about 5 min it was only bypassing steam (not coolant) but I shudder to think what the cooling system pressure got up to, the hoses were hard as rocks. So I'm guessing it was still shooting all that steam into the AST and it had no where to go.

I've resolved to just revert back to the original setup (sealed cap on rad, AST venting to large bottle) and putting in the block seal. I'll run it until the buzzer comes on, release the pressure on the system, and pour the contents of the bottle back into the rad. I figure if I do this 4-5 times, it should equal the 20-30 min run time suggested by the product....nothin to loose right?

 

Looks like we may be in luck....

Here's a picture of the block sealant I picked up, it specifies to put it in a running engine and idle for 20 min or until leaks stop.

Since accessing the coolant geyser while the engine is running wasn't an option I ran it until it was up to temp, then shut down, relieved system pressure poured in 1/2 the bottle of sealant and then topped it off w/ water.

I then ran it until it got up to about 205* (this took about 8 min) and then shut it down. I relieved the system pressure, then poured another 1/8 of the bottle in, poured in the contents of the 1.5 gal overflow, capped it off and then cranked it up.

Ran the engine up 210* (this took about 10 min) and then shut it down and repeated the procedure, adding 1/8 of the bottle and the contents of the overflow tank.

Ran the engine to 207* I stopped because it took 12 min to get there and it appeared that the leaks had stopped..... until I shut it down, and realized that the little leak by the spark plugs was still pissing. So I added another 1/8 plus the contents of the overflow (there was less in the overflow tank each time).

Ran the engine until the leak at the spark plugs stopped (about 5 min) Then let it keep running for another 5 min to see if it would heat up or start acting funny . There was barely any fluid in the overflow so I let it work its way to the crevices for 5 min before relieving the system pressure.

Total run time 40 minutes

I then waited 30 min (apparently not long enough , judging by the burns on my knucles, lol) and drained the radiator and block.

It says to wait "12 hours - (minimum 4 hours)" with drain plugs open before rinsing out the block and filling w/ the appropriate mix of coolant and water


....and so we wait......

 

Really curious to hear the final result. Best of luck.

 

No Dice.

Block weld is a waste of time if you have combustion gasses overpressurizing the cooling system (as I did). Actually, it didn't even seal the external coolant leaks either. If you have a seal that is only allowing coolant into the combustion chamber it will probably work, but other than that, its pissing in the wind.

I'm done dealing with this POS, its going to a shop because I can't afford to throw away another week of my life messing with this damn car.

I'm going to have the engine rebuilt so nothing is left to chance. While I'm at it, I might as well toss in the S5 T2 irons and 9.7 rotors I've been saving.

The few runs around the block I got to do in the 6p-t were impressive. I never boosted, but it felt MUCH stronger out of boost and wanted to try and build boost much quicker than my 8.5cr turbo block. 9.7 rotors w/ 4-port irons should be insane.......so I guess miy 6 port journey ends here.

 

Shame to hear about the motor. Good to hear you liked the 6p-t, i will be going this route in the future as i have near everything needed.

 

Seems like you were doomed from the start. You should try to get some kind of money back. Good luck on your journey man that's rough.

 

Hi


What ECU would you recommend for a 6 port turbo step up? I have a 1989 S5 GTU that I want to turbo with S5 turbo 2 parts.


Thanks

 

I wouldn't recommend you use the S5 NA engine due to the higher compression.

But if you must, at the very least use the S5 or S4 TII ECU.

However the best choice is a full standalone so you can tune it very conservatively.

 

I am aware that some of the FD guys and Eage8 are using 9.7 NA rotors in their builds, but they are starting with turbo engines and swapping in the 9.7 rotors. Are you just not recommending them because they require more conservative tuning, E85, or WI?

I have already read through your whole Project Tina build and have seen all of your Cosmo vids, so I know your experience in this realm is almost unmatched, but I do wonder why you don't use the 9.7 rotors. I would expect that they would have better response at low speeds than the 9.0 rotors and are lighter than the 9.4 rotors, so as long as steps are taken to keep knock down, they should work.

 

Ok that's true. Would my car start and be drivable with primary 550cc, secondary 720cc, stock turbo 2 ecu, turbo afm, and boost sensor? I've seen some of your work and from my understanding you are like the Rotary Yoda lol I've purchased another 13b from a 1989 convertible for a pretty good deal. The guy even delivered it for me. I'm planning to rebuild and turbocharge that one instead.