question:

What is the common failure points of the Thermactor system? I have a 95 f150 5.0 that sounds like it has a manifold leak. It sounds like its coming from the floor board of the passanger side.

At first I just wanted to replace the whole exhaust system, get some shorty headers, a new high flow cat to a single in, dual out the back system from summit. (as cheaply as possible)
Summit Racing SUM-G9035 - Summit Racing® Truck Headers - Overview - SummitRacing.com
MagnaFlow 93312 - MagnaFlow Direct-Fit Catalytic Converters - Overview - SummitRacing.com
Summit Racing SUM-684011 - Summit Racing® Cat-Back Exhaust Systems - Overview - SummitRacing.com

(if you look at this I had some issues finding the right cat for the system. the cat I found that looks right and fits header outlet diameter, but it says its for a 5.8. is this right? Will it fit? does anyone have any thoughts about this? Or part numbers they suggest?)


I still might replace the whole system. BUT after some reading here I think it might acually be the thermactor system.

I got my fat *** all up inside the engine bay and it seems to look like the A.I.R. check valve has been replaced at one time or another because of the screw clamp holding the hose on above it does not look stock.

Is it the check valve leaking? Or maybe theA.I.R. Diverter valve?

Is it possible to delete this system without mayking it look like I deleted it? As I have read, it does not sound like this system is incredible beneficial as power is concerned or once the truck is warm, but I do have emmisions in my area so I would not want to draw attention to that.

Thanks for your comments, it will be very appreciated.

I hope to fix this soon!

 

If you have emissions testing, I would try to fix it. It helps reduce CO emissions. If it's a leak, it should be any easy fix. I've seen a couple smog pumps seize up. To me it sounded like a tea kettle whistling.

 

to my understanding it only helps while the truck is cold. ?

The sound is not quite a high pitch as a tea kettle, but it is very annoying.

 

I believe this system is to pump fresh air into the exhaust to make O2 readily available to convert CO to CO2.

 

The steel tube between the heads at the back of the motor and the check valve attached to it..

 

Thank you conaski, I will replace both. What about the air diverter? does that ever have a tendancy to fail?

does anyone have any comments for the exhaust system I have picked out?

 

thread bump.... any thoughts on the exhaust system I am looking at?

 

As far as I know, it should all work. If you have a sound your are looking for, then you might shop more. Otherwise, go for it.

 

The diverter valves can fail and cause problems too so at least check them out and if they look rough add them to the list.

As for the exhaust you're going to have to use a Y pipe for a 5.0 because the 5.8 motor is taller and wider, you can ignore the inlet diameter listed for them they should all fit the ball socket on the headers, but if for some reason the flange doesn't seat right take the pipe to muffler shop and have them re-shape the flanges in their hydraulic pipe machine.

http://www.summitracing.com/parts/MPE-93307/
http://www.summitracing.com/parts/CTO-9302/
http://www.summitracing.com/parts/WLK-15742/

 

The divertor valve on top of the tube between the heads broke on mine about a year ago. It caused an exhaust leak and sounded really bad. I replaced the valve and problem solved.

I had trouble finding just the valve. Car Quest had it. I think that the local Ford dealer did too. Orielly had the complete assembly, but the valve on it was not removable.

 

Tonight I replaced the crossover tube and the check valve that sits on top of it. When inspecting the tube once I got it out, it acually looked ok. there was some good carbon build up on the inside of it, but very little rust on the out side. The whole job took me about an hour and a half, only because I got a phone call half way through.

There was no discernible change in the sound of the exhaust. It still sounds like it has a leak on the pasenger side. it is just annoying as hell. my wife tells me I am crazy and the truck sounds normal. No disrespect to the woman I love but F that, it annoy's the hell out of me. i

I guess the next step is to either replace the diverter valve, or just replace the exhaust system as a whole with the parts I listed above.

I vote the exhaust system....

What do you guys think?

 

that's probably why she says it sounds normal, because she doesn't want you spending $$ on a new exhaust.

when I did a full exhaust replacement on my 95, I found I had more problems with leaks than before. If you want the new exhaust, go for it, if it's just to get the leak fixed, fix what you've got.

 

Did you put new gaskets where the tube connects to each head?