Silicone hoses for cooling system?

That is a rubber hose to feed hot water to the heater coils up front. You do need to remove the drivers side gas tank to replace that hose.

You do not need to drop the gas tank to replace any of the other cooling hoses. I've done all of them and never had to remove a gas tank to get to them. The only reason you'd need to replace the Al cooling water tube 108081 is if is leaking or cracked somewhere. Even then I think you can get it out with out removing the gas tank. You may have to remove the gas cross over line (PN 115482) but you should not need to remove the gas tank to get the front to back Al. tubes out....

NOTE:
I think Nuvolari was confused in his post above about which Al. hose you were referring too. The tube he is talking about is the connector between the gas tanks (PN 115482).

 

Thanks for the info
now for the inevitable next question, does that hose come as part of the kit from Scuderia Rampante?
If not, any recommendations for what tubing to use and clamps (similar to those from SR)to use? what brand of clamps are they supplying?

Ok, it was 3 questions.....

 

No, SRI supplies a partial hose for the cabin heater hose -- just the section in the engine bay. You splice it in to the rest of the hose running through the rocker panel. The idea was the engine bay portion gets the most wear due to the harsh environment it is in. It's good hose, no doubt, but it would be very expensive to have SRI hose the whole length - it's a bit of a compromise.

Call up SRI and Dave can explain it to you. Otherwise, the kit has all the big sleeves and clamps you need.

I've used the kit on my 328. Expensive, but love it. Best hoses in the business.

The clamps are not Norma clamps, so the look a little diffetent than stock.

 

While I was doing the 308 hoses, I noticed most of the aluminum coolant pipes, (except the long ones through the middle of the chassis), had wear/abrasion marks where they had been rubbing on the corner of the cyl head, or against the right fuel tank and pulley/belt.

Two of the pipes had pin holes rubbed through and were leaking.

So, while you have the chance to remove the pipes, get them out for a good look over. I had my buddy weld the abraded areas, then hooked up the hoses, (with Napa constant torque clamps), left them loose to move them around for the best overall clearances, then tightened up the clamps.

In the case of the right side lower pipe, I clamped a piece of stainless sheet metal as a guard against the belt rubbing, then double-tie wrapped the pipe to the fuel tank strap with a piece of rubber hose in between.

off to work,
chris

 

Just so I won't lose this info.

 

So, I'm getting ready to do this but can't find 40mm Black Silicone hose. Couldn't find any sources here in the US so I went with 1.5 in vs the 1.57 in (40mm). I didn't just drew up did I?

Lester

 

I've found Dayco 77156GL rubber is good at 1-9/16" but hard to find. I had to source 40mm silicone from https://www.autosiliconehoses.com/ in the UK.
Also found that you really have to tighten the clamp on the silicone hard otherwise it will leak.

 

Rant follows:

I'm not a fan of silicone hose for this application. I used it a lot in the marine world and like many things just because a product is really good for certain applications doesn't make it equally good for others. Cooling systems in street cars is one of those 'not great' applications.

Yeah, yeah, I know, "Race cars use it so it must be good!" But like just about everything related to race cars, from oil to tires, that application has almost nothing in common with vehicles driving on the road. Here are two reasons I quit using silicone hoses on most marine applications and wouldn't use them on a car cooling system.

1. Standard silicone hoses are porous compared to conventional 'rubber' cooling system hoses. Coolant will magically disappear over time. Nobody cares about this in a race car - it only has to hold coolant for a few hours and the advantage is that silicone can handle much higher temps than standard hoses...and much higher than you're going to see in any street vehicle. If the temps exceed a standard hose's capability, there will be other damage much more worrisome than replacing a few hoses! The 'coolant disappearing' thing was one of those recurring mysteries for me on marine diesel engines...why did a cooling system need periodic topping off when there were no leaks to be found? Not only were there no leaks, it had silicone cooling system hoses!! Turns out that WAS the problem. Water slooooooowly permeates the hose/evaporates almost instantly - hose is dry to the touch.

More on this point - Silicone is pretty much impervious to damage by fuel/oil. Toss a piece of standard silicone hose in a bucket of oil or gasoline and, a year later it will look just like it did when you tossed it in but it is not used for those applications due to it's porosity. I saw marine diesels need 5 gallons of coolant replaced over a couple of months of operation with silicone cooling hoses. Admittedly, these engines had more hours in a couple of weeks than most of our 3x8's get in a year.

2. Silicone hoses have a recurring need for the clamps to be tightened periodically. If you don't do this, there is a good chance that they will begin leaking at that location after some period of time. Sure, folks can say, "That's no big deal - I'll tighten the clamps once in a while," but if the clamps are somewhat difficult to get to as they are in some cars, it's a PITA. Any particular cars come to mind? Years of contorting myself in boat engine spaces made me a believer in trying to ensure minimal recurring PITA items so installing something that I KNOW will require more maintenance is not high on my preferred list of things to do.

Final note of this rant: An awful lot of silicone hose you will find today on the internet - Amazon, etc - is Chinese made. The Chinese can make a high quality product as well as anybody else BUT marketers are going to buy the cheapest stuff they can from China in order to make a big profit; they are NOT buying top quality Chinese silicone hose. So if you insist on installing silicone hose, buy it from a KNOWN maker of quality hose.

 

Absolutely agree. Not for street car coolant use. Unless you are prepared for yet more maintenance and constant additional worry about coolant level. Only thing I can see is maybe a bling factor if you get blue to go with your blue led lights under the car .