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Overheating - Bypass Hose Coolant Leaking

07-08-2006, 03:59 PM
I noticed that my car is starting to overhead, very very slowling. But when it gets close to 75% to the red zone it really starts to heat up dramatically. I've had the radiator replaced recently and the main hose. I also had a coolant flush, so I kinda knew that wasn't the problem. But I didn't know what the problem was.

I went to a Tuffy today and asked if they could check it. They put a pump where the radiator was at and started pumping. This put pressure on all the hoses. It turns out that the bypass hose is broken (torn, whatever) and it needs to be replaced. He says this a vendor part so it's going to take him a day to get the part. He said that it's probably close to $100 and with labor that I'll probalby spend $200. Now this is just his word, in the end they could charge more.

He said because the hose is behend all these mechanisms that have to be taken off to replace the hose.

Now, does this seem like a reasonable price? If it doesn't how easy (hard) is it to fix a bypass hose. I have a 96 Isuzu rodeo 3.2 V6.


Ramblin Fever
07-08-2006, 05:00 PM
Are you referring to the 90 degree by-pass hose in the front of the engine?

This little hose is about 3-4" long, maybe 5" - it sits at the front of the engine, on top in between the two tops of the timing belt covers?

If this is the hose you're referring to - yes, it IS dealer item only, however, I only paid a whopping $9 dollars for it and it took me 10 minutes to change out, nothing had to be moved to get to it - it's right on the front of the engine.

However, if he's referring to a by-pass hose on the back of the engine - yes, you're looking at spending a bit of $$$ to fix it, those ones are NOT easy to get to and there's a crap load of stuff that must come off to reach them.

At 10yrs of age, yes, it's time for you to replace a lot of your cooling hoses, not just the big upper and lower hoses; but also check your heater core hoses at the firewall passanger side, they're probably toasted as well.

Those two are dealer item's as well - one was $40 and the other $60.

Then there are two coolant/throttle body hoses going up over the top of the engine - $23 for the long one; not sure about the tiny small one as I just caught off a piece of transmission coolant hose and replaced it.

Also, if your truck is an automatic, get your transmission fluid changed as soon as your overheating condition is resolved - these trucks share the radiator with the engine and transmission, if one overheats, they both overheat.

Overheated 4L30-E GM auto transmission = fried transmission.

Post back so we can help you further; if you can take a picture that'd be great.

I just went through replacing a boat load of hoses myself.

I haven't replaced the radiator yet - not showing any signs of needing too, but I'll get taken care of next spring for sure. What was wrong with your OEM radiator?

07-09-2006, 02:24 PM
Ok, here are some pics. Now, when I went to take pictures I couldn't really tell what hose was leaking. I remember vividly that when he pumped the radiator it start squirting coolant and hitting a little mechanism on the engine. A green arrow shows where it was hitting.

That means that the hose under it was leaking. Well that hose looks pretty easy to fix. It goes from the red arrow to the green arrow in this next pic

Now what if it was the next hose below. This hose would require you to do a lot more work.

I have a pic from the bottom of my car that has coolant spilt on this hose. But when i followed the hose it goes stright into the oil filter, which would mean it isn't a coolant hose at all.

I orignall thought that the pan at the bottom had a leak but the Tuffy guys didn't say anything about it. They said it leaked from the top of the engine.

Here's a pic of the overall engine. Ramblin Fever what heater core hoses on the passanger side are you refering too? I don't knw which ones they are.

07-09-2006, 08:59 PM
Coolant hoses do go to the oil cooler on top of the oil filter, I believe.
The third picture is a fuel line.
You can see that you're leaking some ATF in that 4th picture. Check the hose clamps for the ATF lines that run along the passenger side of the tranny to the radiator's ATF cooler.
Take a look with a flashlight at the top front of the engine...way down in there behind the thermostat housing and make sure there isn't any coolant pooled between the heads. That can actually travel all the way to the bottom of the oil pan like in the 4th picture.
I would try to find it myself first, but if it's still overheating, you're still leaking. I eventually took mine to a shop where they discovered a freeze plug leak at the back of the engine.
The heater core hoses are at the back of the engine bay, by the firewall, on the passenger side. They connect to gold metal tubes that then go to the heater core.

Good luck with it all and keep us posted!

Ramblin Fever
07-09-2006, 11:02 PM
Just dawned on me - has your waterpump ever been replaced?

If not, that's a possibility as well - a highly likely possibility if it's the original.

When my 2nd waterpump went out, it was spraying antifreeze EVERYWHERE, and underneith the engine it was mainly pulling at the front of the oil pan, just below the timing belt covers. Exactly where I'm seeing your antifreeze pulling.

Surferfletch pretty much summed up the majority of it; but take a look at your throttle body coolant hoses. That little mechanism you were referring to in the 1st picture is the throttle body, there's a tiny 3" coolant hose (the one you had marked with a green and red arrow) that runs in front of the throttle body - check to see if you're leaking there.

I agree with Surferfletch, you're leaking ATF as well, check your pan bolts, along with your coolant/ATF lines - those OEM clamps on the ATF lines might need to be replaced if they're original.

Same with all of your OEM wire clamps on your upper/lower radiator hoses, check to make sure nothing's wiggled loose, may want to replace them with better radiator hose clamps.

On the 3.2L engine's, there is an oil cooler, in which I believe there are 2 90 degree hoses that connect to the oil cooler on the backside of the oil filter.

These engine's have hoses running everywhere, it about drove me insane when I had a leak I couldn't find.

Keep us posted and good luck.

Ramblin Fever
07-09-2006, 11:04 PM
After looking at your pictures again, I'm bettin you it's either a hose towards the front of the engine, going to the oil cooler, or it's your waterpump going south.

Wanted to add, in your 3rd picture, the hose marked with the bigger question mark - that's the hose going to the top of your oil cooler, that little hose is cheap and easy fixin', also the 1st hose on my truck to go south

07-10-2006, 12:52 PM
Ok, I took my car to the shop this morning (Tuffy). Unfortunatley I'm new to this area, the state really. I moved from Texas to Iowa. When you do that, you loose all your tips and tricks that comes with knowing people. I don't have the luxery of borrowing a car from fam members, while I work on the car, hence i took it in to get it fixed.

What they told me so far. The bypass hose I need is a part that no one has in stock in town, so they're going to used some spares they have and cut it to the correct length. They to removed the theromostat and gasket to get to the core of the problem on the hose. They're replacing the thermostat as well. They said it doesn't need it, but since they're there, they might as well. They said, that all i'll be paying for is parts. It seems like a good idea, since all they would discount me is $15 if they didn't do it. They're also having a coolant flushed, which I knew it would be needed. Current quote $285.00 plus tax. Don't know if I'm being bent, but we'll see. I'll need to see the result.

I'll get back on here and itemize what they've done.

Ramblin Fever
07-10-2006, 01:12 PM
I don't have the luxery of borrowing a car from fam members, while I work on the car, hence i took it in to get it fixed.

Believe me, I understand! I've had to take my rodeo in twice this year because we had no other mode of transportation, and I didn't have time off to work on it. I feel your pain.

Unfortunately, whenever you do have to take it into a shop, you'll always pay a bit more then what could have been had you done it yourself.

Good luck.

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