ntsqd's '71 Wagon

[ntsqd]

Good to talk to you too, Todd. You've really helped fill in the backstory. The Terralow gears are news to me! Thank you for all of your help!

To the best of my knowledge there were two owners between myself and Todd. The guy that bought it from him, and the guy that I bought it from.

Yeller's explanation makes sense. If you don't know about the connector that you need to disconnect on these TBI's then the timing is going to be wrong no matter what you do. Right now the mileage is horrible even for being what it is and the tail-pipe is always sooty black. I've never seen it get warmer than about 140° so I've been thinking that it has either no t-stat in it (unlikely) or a very cold one (more likely). I have the correct t-stat sitting on my desk waiting for me to get the time to replace it.

[ntsqd]

Finally! At least a couple pics of the new wheels.



an aside, notice just how black that tail-pipe is?

[Yeller]

Color me almost jealous, wait not quite, I’m not envious, but so like them I was so close to that exact combination on my truck but wound up with 15x9’s and 33/12.50’s.

No t stat so it was staying in open loop? I may know more than I should and stealing your thunder lol

[ntsqd]

I think that I've mentioned that I drove Patch, the Wonder Yota about 150k on 33-9.50 BFG A/T's and then 33-10.50 BFG A/T's when the 9.50's became impossible to get. I've long thought that they are just about the perfect tire size for long distance desert use.

I've owned exactly one TBI in the past and I didn't have to do any diagnosis on it's engine management, but I do recall that back in the day it was thought that putting a colder t-stat in them, like a 160°, would cause them to run slightly rich with the idea being that you'd get more power. I used to know a guy who actually had an 8 position rotary switch in his coolant temperature sender wires that would allow him to switch between the sensor itself and many different resistors. He claimed that he could get more power out of the engine and increase it's detonation resistance when pulling a grade etc. He'd gone as far as characterizing the resistance of the sender vs. coolant temperature to assign the values of those resistors. What I'd expect from a bored missile testing range technician....

With the formerly working A/C condenser missing and the different radiator in it Mr.Floyd's thought that someone was battling a hot running engine could be one explanation. The area where he lives and where this rig came from can get quite hot, so that someone could have had a problem isn't a surprise. Finding the Stewart Products coolant pump on it was a real bonus. Not sure that all of the moves they made were good ones, but that one was.

H-B for the Blanc-oh has been occupying my evenings so I've not yet had the opportunity to swap out the t-stat.

[ntsqd]

Auto-clanks are no more.

[Yeller]

Auto-clanks are no more.

Party time!!!!

The tstat thing does make a difference. I used to have a 2wd 72 k5... yeah kinda kick myself for converting it to 4wd after 10 years of ownership and beating into a raison, but I have no regrets, I don't do car shows anymore and wouldn't trade the experiences for anything

That truck a hot 350, 10:1 .500" lift cam yadda yadda, it was a load of fun and had a console full of tickets to prove it

Put 280K on it.... but in the summer when the temps got over 85 it would detonate terrible. Could go from a 180 to a 160 and the detonation would go away. when the temps would drop in the fall I'd put the 180 back in so the heater worked.

[devildog80]

Warmer than comfortable with is what I am currently going through with my '84 GW.
And yes I still have the evap cooler in place, and is a consideration to remove, as the A/C is not functional at this time.
Want to keep the York compressor, and rig for onboard air, but right now do not need the A/C as the truck needs to run cooler alone, before I can consider it as a tow vehicle for pulling our camper & gear several times a year up the mountains.
Getting ready to switch out thermostat too, and considering a better water pump. Will research what would be best, but does the Stewart Products pump work good for you?
I have an unknown year 401 engine, and looks like OEM water pump.

I think that I've mentioned that I drove Patch, the Wonder Yota about 150k on 33-9.50 BFG A/T's and then 33-10.50 BFG A/T's when the 9.50's became impossible to get. I've long thought that they are just about the perfect tire size for long distance desert use.

I've owned exactly one TBI in the past and I didn't have to do any diagnosis on it's engine management, but I do recall that back in the day it was thought that putting a colder t-stat in them, like a 160°, would cause them to run slightly rich with the idea being that you'd get more power. I used to know a guy who actually had an 8 position rotary switch in his coolant temperature sender wires that would allow him to switch between the sensor itself and many different resistors. He claimed that he could get more power out of the engine and increase it's detonation resistance when pulling a grade etc. He'd gone as far as characterizing the resistance of the sender vs. coolant temperature to assign the values of those resistors. What I'd expect from a bored missile testing range technician....

With the formerly working A/C condenser missing and the different radiator in it Mr.Floyd's thought that someone was battling a hot running engine could be one explanation. The area where he lives and where this rig came from can get quite hot, so that someone could have had a problem isn't a surprise. Finding the Stewart Products coolant pump on it was a real bonus. Not sure that all of the moves they made were good ones, but that one was.

H-B for the Blanc-oh has been occupying my evenings so I've not yet had the opportunity to swap out the t-stat.

[ntsqd]

I do not yet have enough experience with this engine and water pump to know how well it's working, but I can say that years ago I was fighting a Ford 302 that couldn't stay cool while flat towing the avatar buggy. We live 8 miles from the ocean and to go anywhere is uphill, some of it fairly steep in parts. Putting the Stewart pump on it not only fixed the problem I had to un-do some of the other mods that I'd made because I couldn't get it to warm up in my normal commute. In that process I also learned that those high flow t-stats are not what you want. Unless you have an I-H engine and then they're the only t-stat that you want.

That said, I don't know if Stewart makes a pump for your engine.
https://www.stewartcomponents.com/

[devildog80]

Looked and did not find a Stewart, so ordered one from BJ's, and thermostat to match.

Flow Kooler High Flow Aluminum Water Pump 1973-91 AMC V8
Robertshaw High Flow 180 Degree Thermostat

Might decide to leave evap cooler in place until new WP/Thermostat installed to see if it needs to come out.

[ntsqd]

What I've found with the high flow t-stats is that they don't have as much restriction to coolant flow. That's obvious, what isn't obvious is that a good coolant pump can generate well above cap pressure inside the block. One guy on Classic Broncos did some experiments and it's been a while since I read that thread, but what I recall is that at high RPM it can be above 40 psi. This makes local hot-spots in the coolant jacket much less likely to boil the coolant.

When you reduce the restriction to flow the pump can't generate those high pressures. This part of why running w/o a t-stat or restrictor usually results in the engine running hotter. Without the restriction the pump can't generate those higher pressures and the hot-spots flash the coolant to steam.

That has been my observation and experience anyway. YMMV........

AND, a great theory partly shot to pieces. The t-stat in the Wagon is stamped 195°

[sierrablue]

Maybe your gauge reads in °C

[devildog80]

Well, the best part I can hope for is the 401 engine is documented to have been rebuilt fresh back on 2004, right before it sat for 18 years, and another after I got it home.
PO says about 2500 miles on it, so hoping the block and internals are clean, and will let the coolant flow at speed to keep up with the pump, and not create any hot spots.
Not planning on any high rpm, just driving as a normal DD when running errands and pulling the camper/gear when camping.
Thanks for the insight, and will report back on cooling results, when parts get here, installed, and tested.

[ntsqd]

Maybe your gauge reads in °C

The odd thing is that it's display is about 30% as bright as the rest of the panel. Makes me wonder if it has been damaged somehow.

Well, the best part I can hope for is the 401 engine is documented to have been rebuilt fresh back on 2004, right before it sat for 18 years, and another after I got it home.
PO says about 2500 miles on it, so hoping the block and internals are clean, and will let the coolant flow at speed to keep up with the pump, and not create any hot spots.
Not planning on any high rpm, just driving as a normal DD when running errands and pulling the camper/gear when camping.
Thanks for the insight, and will report back on cooling results, when parts get here, installed, and tested.

The guy who did the block pressure experiments (Yeller, that's "nvrstk" if you're wondering) did them with a very large displacement small block Ford. "High RPM" is likely in the 5K range, not something like 8K.

[tgreese]

Devildog80, have any specs on the rebuild? How much was the bore enlarged? Your typical gray iron block can go for two overhauls of 30 thou each. Due to its close bore spacing, I understand that the rule for 401s is different in this regard.

Ah, 30 over in your sig.

[Yeller]

I’ve read nvrstuk’s thread closely and went on to ask a person I know deep into nascar engines, he r&d’d in depth with the same results. Pump has to exceed t-stat flow and make pressure beyond the cap rating to prevent air bubbles and hot spots.

I usually get looked at like an idiot when I say that. The proof is in science not theories and “I did this” that “cured” the problem when in actuallity they did something they think is completely unrelated that solved the issue and covered up the issues of their “cure”.

[ntsqd]

On a different topic; steering. Clearly the box needs to visit Lee Power Steering. May as well send the pump too. Not sure of when just yet, but it needs to happen. I am tempted to convert the linkage to 1T GM parts while I'm tearing into all of this. Good or bad idea, and why?

Lee doesn't like the plastic reservoirs on those LS type PS pumps. They set them up to be used with a remote reservoir. I just built one of those with engine oil dry sump tank features and have enough parts to build a second one. My aging eyes are making it harder to TIG weld, so the beads aren't as pretty as they could be but it's liquid tight as best as I could test it.

[Yeller]

Nice piece! And I hear ya on old eyes! I’m up to a 2.5 cheater in my hood.

Wish I could figure out how to put a remote reservoir on the bronco with a CBR pump with the resi higher than the pump without reinventing the wheel or just putting it on top of the hood or a feature of the hood lol

For the tie rod ball and sockets are already the same size as the 1 ton stuff, assuming it has stock 74 or newer links. So IMO minimal gain. However as of late the long side link has been troublesome to obtain for both the tie rod and drag link. I know you’re like me and will probably just build links if needed but Rocklaurance on the site here has a bolt on kit, 1 click and it all shows up in a tube ready to install.

https://rocklaurencevintageautoparts.com/products

[ntsqd]

Thanks! That's for the Blanc-oh. Mostly built from parts sourced off amazon with the discs cut out by sendcutsend. My post on GFB about building it: https://www.gofastbroncos.com/forum/vie ... 31#p156531 (I hope that link to another forum is OK.) I have a few things that I'd like to do differently in building the next one.

Well now, that's the Easy Button linkage solution! Likely can't build it for less if my time is worth anything, and it is. Pushed Go! on that.

From my first experience with this Wagon it has done the partial revolution, pause, several revolutions to running type of start. Battery cables are decently sized and look to be in good shape. Engine block to chassis ground was perhaps on the wrong (driver's) side where the battery was grounded to the chassis first near the starter. I moved the engine to chassis ground cable to the pass side, on top of the battery to chassis ground cable and it helped, but didn't eliminate it. A couple years ago I stumbled onto the GM PMGR starters and put one on the '73 SB-SS and have been very impressed with it. Had to search a bit to find an application for this 168t flex-plate, but I'll have one coming shortly.

[Yeller]

Dang it you’re going to force me to register and follow you there like a stalker over there too
love the technical fab stuff. I should document some of mine better, really wish when I was doing a lot of it I had done that.

It’s way more impressive inside. I’m with you most named reservoirs are just wrong, I’d just as soon see it dumped into an extended GM van reservoir.

Back when I was studying steering systems really hard (was looking to be the next PSC before there was PSC) I stumbled on a guy in Australia that ran a trophy truck. He wanted 1 turn lock to lock and not be able to out run it at idle in that off the throttle ohhhh beep moment. It created some crazy gallons per minute flow, can’t remember off hand. The only way he was able to control cavitation was to use a 3 gallon dry sump can as a reservoir and had some baffles in the bottom to prevent the vortex, or technical term, swirly or whirlpool, from sucking air into the pump, like I said the GMP was way up there. So like you I’ve put a ton of thought into those reservoirs.

[ntsqd]

Well.....
Didn't know that was behind a registration. Let's try this:

With the pending H-B conversion I ordered the Saginaw PS pump be rebuilt with a remote reservoir body on it. I plan to return the box and the H-B to the remote res individually. I've long thought that such a reservoir would benefit from having the usual de-aeration methods used in dry sump oil tanks and have sort of been looking for an excuse to try this out. When in college I made some metal spinning forms for a Tooling Class that created the top and bottom of such a reservoir and used Ag sprinkler pipe (tube actually) for the body. I couldn't find them or the piece of the Ag tube that I had so fall back to some alternate plan.
I was never a great aluminum welder, but before my eyesight started to go I could do better than this. Oh well, beats the alternative to aging.....

MISF used one of these to make a coolant recovery tank ($20 on amazon) and it occurred to me that it was just about the perfect size for a PS reservoir:


I carefully cut it at a scientifically arrived at WAG and welded the -10AN bung to the bottom of it.


I wanted the top to have a mild conic shape and I needed the mid-disc to be that way. Ordered some Shore 90A 1/2" thick rubber from McMaster and made a press-forming tool from a rem:


Mid-disc:


I used the same bung and cap that MISF used for his recovery tank. Welded some -6AN bungs to short pieces of tubing and then welded those into tangentially milled cuts in the upper part of the paint cup. The 'candy cane' is a piece of 1/4" aluminum tubing that will become the reservoir's vent:


Shot of the mid-disc and the vent tube - it goes all of the way thru the bottom of the paint cup:


Top section welded together:


Welded assembly: