jammin962

Ok guys, I am new here and I have to say there is some great knowledge, and smart folks, on this site. I have been using the info here the past few days to get into my rig. Now I have to post my findings and see if anyone has any previous knowledge or good advice of what I am dealing with.

I have been searching around here for a few days and haven't seen anything exactly similar, but if this specific issue has already been covered than please correct me and provide the link. Thanks.

MY RIG

1991 - single cab - long bed - 2wd - 3.0 v6 - 1 Ton - auto trans - single rear axle
with about 147,000 miles


THE STORY

Owned her about 2 years and haven't done much but change the oil and drive it. It has had an intermittent coolant leak since I got it. Sometimes engine does not like to run cold (small mis) ONLY if I have not driven it for a day or two AND it is really humid outside. (this only happens on rare occasions cause i usually drive it daily).

Couple days back I hadn't driven it for 2 days and it was quite foggy (moisture) - engine started and cold idled very high as usual and when I dropped into R engine puttered and stalled. check under the hood and nothing unusual ... coolant was low so I started to add some and as fast as I poored it in I could watch it running out from by the thermostat housing area.


I got it to putter into the garage where it is right now (in pieces). I was looking all over with my mirror and flashlight and thought I located the leak at the weep hole for the water pump cover. So I started to tear down to the water pump thinking I could do the swap and have the problem solved.

When I got closer I looked back under the plenum and the intake manifold and saw a puddle of coolant under the intake manifold ... well I tore it all the way down from the top and here is what I find.


th_truck2.jpg?t=1329448527


So, obviously the yellow is old coolant leak and prolly some oil mixed in, it was thick like vaseline. and the front green stuff is the fresher leak. I'm thinking that I had a on going slow leak in the back and then something popped real good.

There are "dividers" on either side of the yellow coolant and it looks like the coolant level recently overflowed these dividers.

th_truck4.jpg?t=1329448527

Here it is slightly cleaned up with pipe removed. I don't find any leaks in the pipe that runs through the middle. (see above pic) My oil and coolant are clean (no HG leak, fingers crossed) All freeze plugs seem to be intact with no visible exterior cracks in the cylinders/heads/water jackets/intake manifold.

The only thing I can come up with is that it looks like the p/o was in here and did a half ace job. There is only a thin layer of RTV on the pipe flange of the coolant pipe that runs down the middle there, and on the block of coolant sensors that bolts to the top of the manifold. also maybe the manifold gaskets were reused...??

I'm not sure, I can't really verify a guaranteed cause of the leak.

I'm kind of in this situation

I think I'm just going to replace manifold gaskets and valve adjust with gaskets, #2 idler/coolant outlet, t-stat, belts, check torque on heads and all that stuff since I'm down here already.

Which brings me to my next question, are there any specific sites that everyone is fond of for getting good deals on good quality yota parts? Good gasket sets? otherwise I'm just gonna order from my local Carquest.

If you made it this far through my lengthy write up here I thank you for reading and any possible advice will be much appreciated.

Thanks.

cman1

iTrader: (1)

Engnbldr.com.

Buck87

Good posting. I reccomend that you put this ito your signature. Also your city in your avitar might help.

jammin962

Location and signature updated!

jammin962

I'm gonna reload those pics a different way and see if they show up any bigger.





not looking very promising ... prolly just small resolution since I took them with my phone? not sure

jammin962

I retract that previous statement ... it worked !!!

toyotabull

My brother had a similar problem on his chevy, which is nothing like your but similar, and after pulling the engine out and swapping in another, he was still losing water. Turns out his intake cracked across the bottom. So if your pipe and intake gaskets seem ok, I would clean up the intake and check it also.

rworegon

Possible source of leak(s): The coolant by-pass tube between the heads is known to get small pinhole leaks, the FIPG/RTV at the tube flange connection fails, or the lower manifold gasket fails near a water jacket allowing the valley to fill with coolant. It looks like you have some oil in there so it appears the gasket is suspect.

Replace the knock sensor wire (dealer only item) while you are in there - it really gets beat up with the heat.

Sealing coolant by-pass tube, page EG2-128. It only seals with a bit of FIPG/RTV and no o-ring.
http://www.ncttora.com/fsm/1993/engine/69cylin.pdf

Here is the same situation on a 5vz-fe:
http://www.tacomaterritory.com/forum...=128424&page=2

jammin962

Time to order up my parts!! I'm excited, but my wallet isn't.

Intake mani looks good toyotabull, I think the leak was (at least partly) the lower intake gasket. In combo with the sealant on the crossover pipe that runs lengthwise down that valley.

I would like to just replace that long pipe even though it looks fine, but couldn't find it on rock auto, guess i'll have to ask the dealer how much it is.

rworegon I will definitely be replacing the pigtail for the ks while i'm down here.. and thanks for the links, the first one didn't work but the 5v did!
and I am doing valve cover gaskets too cause it looks like that's were a lot of the oil is coming from.

Now I need to decide what sealant to use. I found two FIPG p/n's one for the black engine sealing and orange for trans sealing, but not one for the coolant applications. ? .. I read some threads on YT and it seams folks really fancy the Hylomar, the ultra grey, and "the right stuff"...??

Speaking of sealant I tend to use Hi-Tack on cork/paper gasket, anyone recommend any 'dressing' on the intake gaskets since they are metal.?

and finally, what does everyone think about the freeze plugs. Should I change them too since they've obviously been covered in the coolant/oil jelly lake for quite awhile. and is there anything directly behind them in the block that I should watch out for if I drill them out?

Thanks!

rworegon

Link fixed!
FSM states: (b) Apply seal packing to the sealing groove of the water by–pass pipe as shown in the illustration. Seal packing: Part No. 08826–00100 or equivalent

Is this PN what you already have for the FIGP? It's about $60-80.00 a tube from the dealer.

The Right Stuff is good stuff. I've never had problems with Ultra Black RTV though...be sure the surface is very clean (I use acetone) before applying the sealant.

Water by-pass is dealer only most likely - $40-45, I think.

These are online Toyota dealers that sell genuine parts for very good prices:
http://www.toyotapartsales.com/partl...?siteid=214074
http://www.trademotion.com/partlocat...?siteid=214140
https://www.1sttoyotaparts.com/account.html

Do the freeze plugs look rusty?

rworegon

Are you due for a timing belt/WP change?

AZSPEED

mine looked like the wp was leaking but it was leaking in the back where the small hose attaches to the by pass tube it then ran down the tube under the intake and down the water pump. when i took it apart the top on the engine was full of coolant like that

jammin962

well if you look in the pic the 2 freeze plugs that were submerged the longest do show some pitting ... I'll have to go back outside in the morning and take a closer look at them.

I have never changed the timing belt or the w/p on this truck. I've put just under 40,000 miles on it since I've owned it. The timing belt that is on there is not stock, looks like it may have been put on right before I got it. Still looks decent too - no cracks, doesn't look dry, no dusting under the timing cover. I think I may just leave those parts for a project some day in the future.

I already have quite a parts list with all the gaskets and general tune up stuff I'm doing. I think I'm gonna order the bulk of the parts from rockauto.com and some genuine Toyota stuff from one of the links you provided (thanks!)

I was able to find the knock sensor pigtail on the online toyota site, only with the use of the actual toyota p/n that MudHippy supplied in a different thread. Still haven't been able to locate that by pass tube though. I'll be calling the local dealer in the morning to see if they can find me the p/n and price.

All I know is I have to place the parts orders soon, cause I miss driving my yota!

rworegon

That water by-pass tube is typically in the "Radiator and Water Outlet" section on those dealer website part look-up screens.

jammin962

Called the dealer this morning and the by-pass tube is about $114 so I'm just gonna reinstall the old one and hope that there aren't any pinholes or hairline cracks that I can't see.

rworegon

Did you get the part number? 16268-65011, by chance? If so, $63 + shipping online.

http://www.toyotapartseast.com/Page_...3611,3614,3615

jammin962

parts ordered ... I also ordered the by-pass pipe from toyota east. May as well play it safe.

jammin962

I'm going out today to pick up some odds & ends while I wait for my parts to show up at my door. One thing I need to pick up while I'm out is some distilled water and fresh coolant.

So, my question being - should I do a good flush and fill er back up with Toyota red. Or should I just stick to the green, since that's what it's probably had most of it's life.

Opinions?

rworegon

Toyota Red is all I've every used in the truck. It's spendy, but good stuff and does the job as Toyota designed. Some areas only sell Toyota Pink which is pre-diluted.

A few here and elsewhere have used Zerex Asian Vehicle formula, but I've seen no long term reports. I have not used green in so long I cannot give an opinion on it.

fdp101452

most folks will tell you to use red and if i had local access to it i might as well but i dont and have used green for years, but i flush mine every 2 years.