Sound of a header leak

[TheCatsRV]

Drove home a '07 V-10 Coachman Mirada (just ~30 miles but with a ~1,000' climb and descent). As I drove the last few miles, I noticed that there was a puffing sound whenever I applied throttle. Sound wasn't there when I started out or test drove the right last weekend. The rig does have Banks headers. Would it be a good assumption that the sound is a header leak? Start by tightening bolts (and is there a torque pattern?)


Haven't worked on engines in several years, and never a Ford.

[donr103]

It could be spark plug.. v10 known to spit them out.. tool is expensive and requires good hands and skill.. some auto part stores may loan tool for free.. you could try that.. but warned.. if you mess up.. you may need to pull head and take to machine shop.. use stethoscope to probe for leak.. you can buy car stethoscope for under 20 and listen exactly where leak is.. even if headers.. you are still going to have to replace gasket.. tighten might help for very temp fix.. but that big eng will just blow through where you tighten it.. so ONCE you find leak.. if header.. you need to pull it and install new gasket.. you may want extra hands.. get them gloves.. good luck and let us know what you did and maybe better members then me will help you

[TheCatsRV]

The chassis is an '06 so should have the heads with a deeper thread? Transmission has the tow/haul button and I understand the 5 spd have the 3-valve motor? Thanks for the stethoscope idea. I will see if there are loose header bolt first.

[TheCatsRV]

Just occurred to me the prevous owners had the starter motor replaced just over a week ago. I am hoping the header just wasn't tightened properly when it was reinstalled.

[HarryStone]

Originally Posted by TheCatsRV

The chassis is an '06 so should have the heads with a deeper thread? Transmission has the tow/haul button and I understand the 5 spd have the 3-valve motor? Thanks for the stethoscope idea. I will see if there are loose header bolt first.

Yes.. it will have the improved heads.

[donr103]

If starter was replaced.. you forgot to mention that... yes try to tighten bolts.. I start inside bolts 1st and work to outside bolts next.. like.. two most inside.. next two most outside.. next the outer ones.. that's how I do it.. also.. you could take bolts out and use antiseeze on them 1st, one at time.. so if you need to remove latter they might be easier.. or get new SS. Bolts.. because if you plan to keep.. you may have to take them out latter.. also get a starter blanket to keep starter from burning up.. good luck and keep us posted

[TheCatsRV]

I took a look today. All the bolts (couple of studs weren't changed out) seemed tight.


Where the flanges meet the cylinder heads (both sides) seem shiny and sootless.


https://1drv.ms/u/s!AnrZHGaAwtashJRy...SKSWw?e=cVDeN1


Looks like the starter (whicch has a heat shield) can be changed w/o removing headers (tubes go straight back).



Wondering if it could be leaking at the collector(s)? One doesn't seem to line up that well (have to find a picture host - what does everyone use?).


I guess I will have to go buy a stethoscope as suggested.

[Hpozzuoli]

I doubt it has anything to do with spark plugs. Yes it’s a 3 valve with the plugs way down in the valley. Yes they break sometimes when you try to remove them after 100k miles. Yes there is a special tool to remove broken plugs. Change them early and often and have no issues.

Back to the noise…..sounds like exhaust leak to me.

[TheCatsRV]

Ran the motor briefly on the premise hat sparks supposedly can be seen. No sparks when I had my wife rev the motor lightly). Felt the head/header joint, just radiant heat from the headers.


Went to feel around the collector joint in question and felt what fells like hot gas

[TheCatsRV]

Used the shop vacuum cleaner as a blower today and blew air into the exhaust. Leaky (actually burnt) gasket, last cylinder on the driver side. Gaskets seem easy to get. Any suggestion on which bolts? Most at Jegs or Summit are steel zinc-plated at best (no S/S for Ford, mostly for Chevy and some for Mopar) or I maybe able to get Dorman s/s studs + nuts here.


Fel-pro premium gaskets; will they do?

[TheCatsRV]

Ended up supplying Mahle gaskets and Dornan copper studs to a fleet Bus/truck/RV maintenance centre to red the headers. A few broken studs including two on the leaking cylinder that needed to be helicoiled.