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Engine Specific Info and Questions => IDI Engine => Topic started by: Gizmoman on April 29, 2013, 06:44:07 pm

Title: Thermostat questions
Post by: Gizmoman on April 29, 2013, 06:44:07 pm
OK, I posted this befoere under a different heading but I wasn't getting any response so I figured I try a different angle. . .

I'll be replacing the thermostat as part of my AAZ rebuild and after doing some searching here, I can't find what I'm looking for.
The one that was in the motor has 82c stamped on it - made by WAHLER in Germany. It does have the hole with the loose brass thingy.

The distance from the rim of the brass body to the seat plate is about 1.25. The depth of the seat inside the pump housing is 1.47. In other words, this never did close entirely (not sure if it's supposed to). I have found other brands that are listed for this engine but they all have the same dimensions (at least those that list dimensions). Obviously I'm missing something and if someone knows the reason why it's a 1/2" shy of seating, that would be helpful.

Another odd thing is that the new o-ring doesn't feel like its going to provide enough "squish". The cast aluminum cover looks like it's against the pump housing even before I tighten the two tiny bolts. I spo'ze I could smear silicone all over it but I don't want to go there just yet.

Is there a different seal I need rather than the o-ring that came with the new pump? The one I removed has a rectangular cross-section - I'd use it again but it seems a bit brittle.

Any feedback appreciated.
Title: Re: Thermostat questions
Post by: wolf_walker on April 29, 2013, 07:07:18 pm
As I recall the t-stat is the same on all those motors, which housing are you using?  New complete waterpump or the housing off the AAZ originally with a
new pump insert?  I swear I don't remember the whaller having the brass check valve like that but I could be wrong.  I'm pretty sure 87 is stock but
wouldn't bet my life on it right this sec.

Yeah no bypass valve in any recent production one's..
\https://www.google.com/search?q=056121113D&safe=off&source=lnms&tbm=isch&sa=X&ei=jCd_UcHxNsPHiwKa6oDYCw&ved=0CAoQ_AUoAQ&biw=1920&bih=910#safe=off&tbm=isch&q=wahler+056121113+D&spell=1&sa=X&ei=lid_UZv4FqWIiwLm9IHACw&ved=0CE8QBSgA&bav=on.2,or.r_cp.r_qf.&bvm=bv.45921128,d.cGE&fp=3f8fec3d872e59f8&biw=1920&bih=910
Title: Re: Thermostat questions
Post by: Gizmoman on April 29, 2013, 08:56:37 pm
Thanks Wolf.
I bought the whole pump, housing and all. The repair part was 38 and the whole pump was 64 so I just went for new.

. . .I just realized how it actually works - man do I feel stupid :-[

Oh well, I still don't like the way the seal fits. Do you know if there was ever a square section rubber seal instead of the O-ring?

I think ideally, it would be a square section rubber ring with a thin groove around the ID that the brass flange would fit into. That "assembly" would drop in (and center better) and also provide a good seal. As it is, I have serious doubts that it would seal at all.

BTW, I tried to copy the link you pasted but it doesn't seem to work.

Thanks for the feedback.
Title: Re: Thermostat questions
Post by: wolf_walker on April 29, 2013, 09:34:00 pm
https://www.google.com/search?q=056121113D&safe=off&source=lnms&tbm=isch&sa=X&ei=jCd_UcHxNsPHiwKa6oDYCw&ved=0CAoQ_AUoAQ&biw=1920&bih=910#safe=off&tbm=isch&q=wahler+056121113+D&spell=1&sa=X&ei=lid_UZv4FqWIiwLm9IHACw&ved=0CE8QBSgA&fp=1&biw=1920&bih=910&bav=on.2,or.r_cp.r_qf.&cad=b&sei=5Uh_UYOBD6O2iwKkqYHoAw (https://www.google.com/search?q=056121113D&safe=off&source=lnms&tbm=isch&sa=X&ei=jCd_UcHxNsPHiwKa6oDYCw&ved=0CAoQ_AUoAQ&biw=1920&bih=910#safe=off&tbm=isch&q=wahler+056121113+D&spell=1&sa=X&ei=lid_UZv4FqWIiwLm9IHACw&ved=0CE8QBSgA&fp=1&biw=1920&bih=910&bav=on.2,or.r_cp.r_qf.&cad=b&sei=5Uh_UYOBD6O2iwKkqYHoAw)

Sorry I messed up the first link, extre / on the start of it.

Anyway, the seal as I recall goes on the cover/hose flange with the thermostat up in the housing.  It isn't impossible you have a crappy o-ring I guess but I've never had one leak other than with badly corroded aluminum flanges.  I have one in the shop I'll check later if nobody else jumps in.
Title: Re: Thermostat questions
Post by: Gizmoman on April 30, 2013, 06:53:57 am
Thanks Wolf. Yup that's the puppy and all O-ring seals - hmmmmm.

I will have to do the silly-cone thing I guess cause I really don't trust that seal. I have several new O-rings and they all fit the same.
The cap is good (not corroded) and the pump housing is brand new.
I'll measure the depth to the seal seat on the old pump housing and see if that's the issue - damn, always somethin'!

. . .  OK, .260" on the old, .0273 on the new = near zero squish (on the new housing) - crap - this really sucks.
Title: Re: Thermostat questions
Post by: wolf_walker on April 30, 2013, 09:59:20 am
Something somewhere is wonky, I've never had to fight with one of those to seal.
Title: Re: Re: Thermostat questions
Post by: vanbcguy on April 30, 2013, 11:39:29 am
Aren't there two O-rings? Or am I remembering weird?

Sent from my HTC One X using Tapatalk 2
Title: Re: Thermostat questions
Post by: R.O.R-2.0 on April 30, 2013, 12:53:15 pm
Get a t-stat o-ring for an 80s - 90s 4cyl toyota pickup..

i HATE the oem VW o-rings..

the toy o-ring sits around the edge of the t-stat, and seals it from both sides...

never had a single leak, using the yota style t-stat o-ring..

its the same thickness and diameter as the VW unit, but it sits around the edge of the t-stat, instead of just sitting on the face of the t-stat..

plus, once you get the t-stat up in the housing, the yota o-ring is enough bigger that it actually holds it in place as you install the water neck..
Title: Re: Thermostat questions
Post by: wolf_walker on April 30, 2013, 01:28:32 pm
Nice tip!

Title: Re: Thermostat questions
Post by: R.O.R-2.0 on April 30, 2013, 01:55:24 pm
Nice tip!



order the o-ring for an 85-94 toyota pickup/4runner w/ (22r(e) engine..

i believe the V6 trucks used the same o-ring, but im not positive, so just get the one for the 4 cyl..

last time i bought some, they were $1 each, so i bought an entire box..
Title: Re: Thermostat questions
Post by: smutts on April 30, 2013, 02:48:50 pm
Quote
plus, once you get the t-stat up in the housing, the yota o-ring is enough bigger that it actually holds it in place as you install the water neck..

Did I ever loathe the design, it seemed one was supposed to roll the car over onto its roof to keep the thermostat and seal dislodging as you put it together. I never got the knack, I just superglued the sodding squalid thing in place so it could then be bolted up. >:(

P.S. Thanks to R.O.R-2.0 for the tip ;)
Title: Re: Thermostat questions
Post by: R.O.R-2.0 on April 30, 2013, 02:52:24 pm
Quote
plus, once you get the t-stat up in the housing, the yota o-ring is enough bigger that it actually holds it in place as you install the water neck..

Did I ever loathe the design, it seemed one was supposed to roll the car over onto its roof to keep the thermostat and seal dislodging as you put it together. I never got the knack, I just superglued the sodding squalid thing in place so it could then be bolted up. >:(

i was a yota mechanic before i was a VW mechanic, so i had LOTS of those o-rings laying around..

i really hated the design as well, so thats what made me think of using the yota o-ring..

most guys pull the top rad hose from the engine, and hook a shop-vac up to the water neck.. i never liked the idea very well, so i just use the yota o-ring..
Title: Re: Thermostat questions
Post by: Gizmoman on April 30, 2013, 05:28:55 pm
Get a t-stat o-ring for an 80s - 90s 4cyl toyota pickup..

i HATE the oem VW o-rings..

the toy o-ring sits around the edge of the t-stat, and seals it from both sides...

never had a single leak, using the yota style t-stat o-ring..

its the same thickness and diameter as the VW unit, but it sits around the edge of the t-stat, instead of just sitting on the face of the t-stat..

Awesome - EXACTLY what I was looking for Mr!
As I said earlier in this post
Quote
"I think ideally, it would be a square section rubber ring with a thin groove around the ID that the brass flange would fit into. That "assembly" would drop in (and center better) and also provide a good seal. As it is, I have serious doubts that it would seal at all."
plus, once you get the t-stat up in the housing, the yota o-ring is enough bigger that it actually holds it in place as you install the water neck..[/quote]
(http://s4.hubimg.com/u/4257843_f260.jpg)

Done dealeao ;D
Title: Re: Thermostat questions
Post by: R.O.R-2.0 on April 30, 2013, 09:11:55 pm
Im sorry i didnt chime in earlier...
Title: Re: Thermostat questions
Post by: Gizmoman on May 01, 2013, 05:40:40 am
Im sorry i didnt chime in earlier...
all is forgoven

This needs to be added tin the sticky notes somewhere
Title: Re: Thermostat questions
Post by: R.O.R-2.0 on May 01, 2013, 11:20:14 am
i guess i just assumed EVERYONE ran toyota t-stat o-rings on these things..

lol..

ive beem running this type of o-ring for soo long, that i forget ive gotten them in the car till i pull the t-stat..

ive also re-used them many, many, times, without issues..
Title: Re: Thermostat questions
Post by: Gizmoman on May 05, 2013, 10:03:40 am
Here's a shot of the thermostat with the toyota seal installed - Thanks R.O.R.
i guess i just assumed EVERYONE ran toyota t-stat o-rings on these things..

lol..

ive beem running this type of o-ring for soo long, that i forget ive gotten them in the car till i pull the t-stat..

ive also re-used them many, many, times, without issues..
I don't think it's tight enough in the housing to stay put if it's upside down but it is centered much better and it will definitely seal!
(https://lh4.googleusercontent.com/-di0t0G5jDOk/UYaMqw1yk4I/AAAAAAAABsI/CHnE5jsW1rI/s720/DSC00454.JPG?gl=US)
(https://lh4.googleusercontent.com/-H9UbCOagzXw/UYaMqdrcyYI/AAAAAAAABsE/QILWyDDDhso/s720/DSC00455.JPG?gl=US)
Title: Re: Thermostat questions
Post by: R.O.R-2.0 on May 05, 2013, 11:31:13 am
oh, it'll work!!
Title: Re: Thermostat questions
Post by: wolf_walker on May 05, 2013, 11:38:18 am
Your t-stat has the wrong country stamped on it.  ;)
Title: Re: Thermostat questions
Post by: R.O.R-2.0 on May 05, 2013, 11:44:03 am
Your t-stat has the wrong country stamped on it.  ;)

has it been boil tested?

i test every thermostat i install in a car, new or used..

more often than not, i have better luck with used OEM t-stats, than brand new McAutoparts t-stats..
Title: Re: Thermostat questions
Post by: Gizmoman on May 05, 2013, 12:45:04 pm
No, I didn't test it but I did drill a tiny bleed hole in it which I pointed upwards once the engine is in.
Title: Re: Thermostat questions
Post by: R.O.R-2.0 on May 05, 2013, 05:59:28 pm
No, I didn't test it but I did drill a tiny bleed hole in it which I pointed upwards once the engine is in.


well, thats a step in the right direction..