Coolant bypass.

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Cleat
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Coolant bypass.

Post by Cleat »

The 2.9 in the Ranger has no bypass hoses and uses the heater as a bypass. Is there a reason the Scorpio uses them ?

The reason I ask is the timing chain cover on my Scorpio 2.9 has very badly corroded through hose fittings and I want to simply weld them shut.

Just thinking out loud.

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Cleat
Last edited by Cleat on Wed Nov 16, 2016 9:04 pm, edited 4 times in total.
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John Brennan
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Re: Coolant bypass.

Post by John Brennan »

You mean...the coolant flow is continuous through the core?
Blasphemy...
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brokencase
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Re: Coolant bypass.

Post by brokencase »

Cleat, I would look for a good used cover. Either in the local yards or keep eyes peeled on Ebay or Craigslist
..or perhaps a board member here can sell you one.

I say this for two reasons:
1) You may have other areas of corrosion on the cover that could become a concern later on..
2) You are only asking for trouble when you start disabling the heater/bypass.
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Re: Coolant bypass.

Post by Cleat »

I am not bypassing the heater (a needed item here in Canada) only the bypass hose to the water pump from the lower intake.

It was done on all Ford Rangers so I don't see the problem (not that there isn't one). The hearer control valve has been deleted already.

This is a 2.9 Scorpio engine transplanted into a 1985 XR4Ti.
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Re: Coolant bypass.

Post by DPDISXR4Ti »

Bumping this thread as I'll be doing a coolant system "update" on the Scorpio this spring. I'm all about simplifying things, so the HCV will be getting ditched for sure. Wondering about the coolant bypass hose discussed herein and if/how that could be ditched.
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Re: Coolant bypass.

Post by DPDISXR4Ti »

Trying to figure the Scorpio coolant flow strategy. Pics below are from my partScorpio which is a '89 factory 5-speed. Is the capped off fitting on all Scorpios or is this just a 5-speed thing?
ScorpioBypassHose-1.JPG
ScorpioBypassHose-1.JPG (963.27 KiB) Viewed 2203 times
ScorpioBypassHose-2.JPG
ScorpioBypassHose-2.JPG (950.48 KiB) Viewed 2203 times
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Ed Lijewski
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Re: Coolant bypass.

Post by Ed Lijewski »

It's an '89 model change (auto and manual trans).

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Re: Coolant bypass.

Post by DPDISXR4Ti »

Ed Lijewski wrote: Tue Mar 03, 2020 8:33 pm It's an '89 model change (auto and manual trans).
Hmm, so did the Scorpio basically go with the Ranger 2.9 strategy but instead of going with the Ranger cover they just capped it off? Ranger cover below....
Ranger29TimingCover.jpg
Ranger29TimingCover.jpg (57.42 KiB) Viewed 2175 times
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andyofcolumbusmerkur
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Re: Coolant bypass.

Post by andyofcolumbusmerkur »

I had an old Jeep, and previous owner had installed two pieces of garden hose going from the engine straight to the heater core. It was an open top/bikini top cj7 and it was still uncomfortable in the summer with that hot coolant flowing around near your legs. I've seen people put some valves near the firewall on an xr with bypassed control valve, at least you could shut off the flow in the summer if needed. I think as long as there was some flow going around the closed thermostat, like out the 1/4 inch sized hose at the filler neck, you would be fine and not hurt the engine. I'd imagine the ford engineers were concerned with a hot spot starting near the combustion chamber, before the thermostat had a chance to open. You know how people drive, starting a completely cold engine and immediately flooring it, 45 seconds later doing 90 on the highway.
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Re: Coolant bypass.

Post by DPDISXR4Ti »

andyofcolumbusmerkur wrote: Wed Mar 04, 2020 9:41 am I had an old Jeep, and previous owner had installed two pieces of garden hose going from the engine straight to the heater core. It was an open top/bikini top cj7 and it was still uncomfortable in the summer with that hot coolant flowing around near your legs.
Myself and others have run without a HCV in a XR for years. No issues. My Alfa 164 came without a HCV from the factory. No issues. Sure, there's going to be some incremental heat that transfers into the cabin, but with the flapper valve closed, the effect is minimal.

But that's not the focus of the conversation here. We're talking about the coolant flow through the front timing cover. Look at my pics above. Looking at BAT's old catalog, this isn't even indicated at all.
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Re: Coolant bypass.

Post by DPDISXR4Ti »

Stopped off at a junkyard on the way to Carlisle last month and came upon a '89 2.9 Ranger that was significantly disassembled. I knew this was my chance to get a front cover, so I went to work. Even with all that was removed, it was no walk in the park. The crank pulley had likely never been off the engine in 30+ years so it took a lot of work with a hammer and pry bar. Thankfully I didn't need that since I killed it in the process. In the end success....

Here's what I found....
Ranger1989-1.jpg
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Ranger1989-2.jpg
Ranger1989-2.jpg (350.82 KiB) Viewed 368 times
Ranger1989-3.jpg
Ranger1989-3.jpg (311.93 KiB) Viewed 368 times
And here's what I ended up with after a significant effort with the power washer once home...
Ranger29Cover-1.JPG
Ranger29Cover-1.JPG (1.07 MiB) Viewed 368 times
Ranger29Cover-2.JPG
Ranger29Cover-2.JPG (1.08 MiB) Viewed 368 times
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Re: Coolant bypass.

Post by my8950 »

If there is something off a Scorpio that you're looking for, let me know.
I've got one here that I am taking apart as it's rusted out.
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Re: Coolant bypass.

Post by DPDISXR4Ti »

my8950 wrote: Fri Aug 28, 2020 5:39 pm If there is something off a Scorpio that you're looking for, let me know.
I've got one here that I am taking apart as it's rusted out.
Thanks, but I've got a parts Scorpio here as well. The front cover off the Ranger 2.9 is different - that's why that needed to be the donor. I still haven't researched enough the differences between the coolant routing on the Ranger and Scorpio to know for sure if I'll even use this, but there's a good chance I will so I had to seize the moment.
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Re: Coolant bypass.

Post by DPDISXR4Ti »

I haven't done anything on researching the use of the Ranger 2.9 front cover, however, driving the Scorpio a couple times lately in colder temps I have been impressed with just how quickly the heat comes up. In fact, I'd say it's faster than any vehicle I own, some of which are much more modern rides. I'm wondering if perhaps the different plumbing of the Scorpio (vs. the Ranger) is responsible for this.

Just a thought...
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Re: Coolant bypass.

Post by Ed Lijewski »

I agree re the Scorpio heat, but I find the XR heat comes up quite readily too.

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