Heater hose from water pump to heater box

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Theduke
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Joined: Thu Feb 13, 2020 8:08 pm
Location: South Carolina

Heater hose from water pump to heater box

Post by Theduke »

So I had to replace my water pump, then radiator, basically the whole cooling system and figured I'd replace all the old hoses also.
Here's my problem old heater hose is 3/4 so I bought new 3/4 replacements. However it will not fit on the new water pump. I cannot verify as I threw the old pump away but my assumption is the old outlet was straight wall and the new pump does have a flare at the end. How do I get the new 3/4 line over the flare. I've tried Vaseline and I've tried putting a cone in the end to expand it some and neither worked.
Suggestions?
Thanks
1989 Grand Wagoneer
AMC360 TF727 NP229
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babywag
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Location: Land of Fruit Loops & Coconuts

Re: Heater hose from water pump to heater box

Post by babywag »

Is new pump cast iron?
Many are just junk castings right out of box.
Horrible finish/fit...
Wrong size or so rough they leak like crazy even with new hoses/clamps.

I had to use an aftermarket 1"-3/4" hose and a tee fitting once.
Casting was like 1" for that hose and zero chance getting a 3/4" hose on there.
Found hose by just scoping all hoses hanging in back of parts store.
-Tony
'88 GW (aka Babywag)
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tgreese
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Location: Medford MA USA

Re: Heater hose from water pump to heater box

Post by tgreese »

Supposedly the GMB water pump is ok.
https://www.rockauto.com/en/catalog/jee ... +pump,2208

Suggest you buy the better quality pump and either eat the cost of the bad replacement, or try to get your money back.

Also, it is a common rookie mistake to throw away or turn in for exchange your old parts before the job is completely done and tested. Usually it's rebuilt/remanufactured parts and the buyer turns in a core for exchange at the time of sale. They discover that the new part won't fit, of some pieces aren't included, or some similar problem. They come back a day or two later to the store and want the core back, but it's gone. Turning in your core is just like throwing it away in this respect - it goes into a big pile of cores that are typically broken down for "remanufacture." No tracking, no way to recover. If you exchange, take all the time they will allow, or just don't claim the core charge and keep the core indefinitely.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
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Theduke
Posts: 44
Joined: Thu Feb 13, 2020 8:08 pm
Location: South Carolina

Re: Heater hose from water pump to heater box

Post by Theduke »

The new water pump is an upgrade to the old one from Bjsoffroad. The issue is that it has a flare at the end and I can't get the 3/4 hose over the flare. My buddy said he ran a short piece of hose the next size up and used a connector between the 2 sizes on his cj5. I'm asking if anyone has advice on getting the 3/4 hose over the flare.
1989 Grand Wagoneer
AMC360 TF727 NP229

rocklaurence
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Re: Heater hose from water pump to heater box

Post by rocklaurence »

Dip the end of the hose in Hot water to soften it up? Ive never had that issue. I do know that I put my hose on before the AC/Alternator brackets because access is so limited.
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tgreese
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Re: Heater hose from water pump to heater box

Post by tgreese »

You have installed the water pump and now find you can't get the hose over the nipple? And don't want to go backwards with a different water pump?

Silicone heater hose might stretch enough to go over the nipple. Not cheap.

Tony suggested above that you look for a molded heater hose that goes from 1" to 3/4" and use that. He found one with the help of his friendly local parts store.

Dorman makes adapters and couplings for heater hose - https://www.summitracing.com/search/bra ... e/straight - Dorman has a web site www.dormanproducts.com and you might find a 1" to 3/4" connector so you can use a short piece of 1" heater hose. RockAuto shows both 7/8" and 1" heater hose in bulk; you might be able to buy a short length of hose to use with a coupling at your local truck or boat supply. https://www.rockauto.com/en/tools/hoses ... pe,1001645

Rock Auto also has a bunch of different fitting and hoses you can look through. You have lots of possibilities to explore if you are determined and resourceful.

LATER - I would also mention, that the heater hoses are something that frequently fails and strands motorists. Usually it's because the hoses are so old that they fall apart, and people never change them. The generic hose that many stores sell today seems very low quality, And I would replace it all every year or two. Certainly I would use new hose with a new water pump. Gates seems pretty good, and they have a couple of upgraded lines: Barricade and Green Stripe. You should be able to buy Green Stripe at your local over-the-road truck supplier.

Anyway, having to stretch the hose over a too-large nipple would not inspire me with confidence. I would expect the strain at that connection would make that spot a focus for failure of the hose.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.

letank
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Joined: Wed Oct 03, 2012 9:16 pm
Location: SF bay area

Re: Heater hose from water pump to heater box

Post by letank »

file the offending nipple enough to slide your hose>
Years ago I had to do it because the fitting was not round enough
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)
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