I am changing the coolant hoses on my 91 convertible NA. Is it possible to change the hose that goes from the TB to what looks like the backside of the engine block without removing the Intake manifold? If I do have to remove the manifold what gackets will I need and is there anything else I should replace while I am in there?

One of my coolant hoses blew on me when I was driving home from an AutoX on March 17 so I am changing all the hoses. I managed to cut off the broken section on the side of the road and a lady brought me some water in 1 gallon pickle jars.

 

as long as you can get your fingers in there to pull the line off you can do it with out takign the intake manifold off. but if you have to take it off...just remove the upper from the lower intake mani. keeping the TB attached to the upper, then you would only need the gasket that is between the upper and lower....and if i type upper and lower again im gonna cut my fingers off

 

If you have to take off the manifold, I'd replace the vacuum hoses (if you haven't already), make sure the OMP lines are in good condition (very fragile), check the splitter for air leaks, cap off the hose that goes to the AWS solenoid, as well as the cap off the nipple that it connectos to on the TB, and most importantly, send off the injectors to be professionally cleaned... and replace the injector grommets with ones made from 10mm silicone vacuum hose.

Replace the intake manifold gaskets with new paper ones, but put RTV on them to make them easier to remove next time you have to take it off.

You might not have to take the manifold off to get the hose, if you can reach and undo the clamps without taking it off....but it would make it a whole lot easier to do so.

 

**********8
Location: South Carolina
Posts: 20 How to remove Coolant hose from ThrottleBody to engine block

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I am changing the coolant hoses on my 91 convertible NA. Is it possible to change the hose that goes from the TB to what looks like the backside of the engine block without removing the Intake manifold? If I do have to remove the manifold what gackets will I need and is *************8


Yes.

 

**********8
Location: South Carolina
Posts: 20 How to remove Coolant hose from ThrottleBody to engine block

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I am changing the coolant hoses on my 91 convertible NA. Is it possible to change the hose that goes from the TB to what looks like the backside of the engine block without removing the Intake manifold?


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Yes.

 

I will try to get the hose since some people have managed but it is awfully tight in there to try and get that clamp. To bad St. Patricks day is over because I could have used a leprachaun to do it.

I would also like to say the rolled hoses that Napa sold me are to small. 5/8, 5/16, and 3/8 for the heater core and throttle body

 

Well, the OEM hoses are pre-bent so that they fit nice and easy... ideally you'd want to use those.

 

home depot hose ftw!

 

Well, I had to remove the intake manifold. The clamp was put on at 180 deg. the wrong way.

Where can I get 10mm silicone hose? Are there any common local sources?

Why do I want to cap off the AWS solenoid?

Why do you recommend cleaning the injectors? Is this a common issue with Rex's?

 

Because the AWS is a worthless piece of crap.

I haven't sentmine off to get cleaned, but one place I've heard of is RC Engineering. It's not that it's a common issue... it's just that after 15-20 years, injectors get dirty, and it's not always something you can clean with fuel system cleaner. This applies to all cars.

Personally I just got the hose from Mazdatrix...you can order it the same time you order an gaskets.

 

AWS being worthless does not say much. Does it not work correctly or does it take away some horsepower?

I was just going to buy the gasket at the dealer. Mazdatrix is kind of expensive. I would like to try the silicone hose but am not sure if I can get it locally anywhere. What are the advantages of the silicone hose over the oem seals? The originals seem to have lasted 111,000 miles and not leaked yet.

 

The AWS makes the engine rev to 3000 rpms when it's cold. That's not good for the engine. It was basically designed to heat up the cat as fast as possible for emissions reasons. Revving like that, as soon as the engine turns on, is a bad idea IMO.

Hell, the BAC will do it by itself anyway, so you might as well remove the 20 year-old vacuum lines (they are big and pre-shaped, so people don't tend to replace them) under the UIM that go from the solenoid to the air splitter.

Mazdatrix's prices are less than dealer prices. The only difference is that you have to pay for shipping, and it takes a few days longer to get the parts.

You can get the hoses from any local performance shop...probably.

According to RETed, the OEM ones will get hard after just a few thousand miles, whereas silicone will stay soft and seal better, longer.

And it's not that they haven't leaked... it's just that you either haven't noticed it, haven't detected, or they simply haven't got around to it. Preventative maintenance goes a long way to keeping a car running, and you already had to take the UIM off anyway, so you might as well clean and get new grommets for the injectors...

Hell, you should really replace the fuel injection lines (DON'T use fuel lines... those are for carberated engines), as well as get some proper fuel injection clamps. Just because they aren't leaking now doesn't mean they won't. I was lucky and noticed the big trail of gasoline training behind my car when mine decided to have a massive leak (under the UIM of course). Taking the UIM once and replacing everything under it is a lot easier than taking it off 5 times every time you have a different problem.

 

I was not saying that I did not want to replace them; I was saying that replacing them with oem seemed adequate. The dealer quoted me $59 to replace all 5 seals on the 4 injectors. I thought that was kind of high for orings and grommets. Plus it would be until at least Tuesday.

 

BTW, the silicone hose is only for the lower grommets...not for the upper ones or the o-rings.

Also, replacing the lower grommets is to prevent vacuum leaks, not to prevent fuel leaks.

 

If you're going to spend that much for just the seals, you might as well send the injectors off to Cruzinperformance.com and have them professionally cleaned and tested. All O-rings and seals will be replaced as well. And all that will cost you just a bit more than the $59.

 

I think I am going to replace what I can now and just put the car back together today. I don't want to have this car not running for another week. I have work to do on my other cars.

My friend sent his BMW inectors to get cleaned and one came back nonoperational. It was some place in California.