Exhaust gaskets

Hi guys, one issue I have been having is selecting suitable exhaust gaskets to fit between the engine and the headers.

I have a GPZ750A1 83 model.

I purchased a set of copper ones which fitted nicely over the end of the header pipes, but a not so subtle flash when I turned over the engine indicates I may have gotten it wrong.

Another thing is that the exhaust is a real pain to put on - there are I suppose brackets which hold the exhaust onto the engine, but inside these brackets there are like sleeves which seem to allow for a better fit - but don't really do the job all that well.

The whole thing seems a bit dodgy and Im not surprised at the results Ive been getting. I was thinking of using some hi-temp silicone or something to fill in the gaps.

I dont want to buy a new exhaust just yet, but I believe that will be on the cards eventually.

What tips does anyone have with fitting and exhaust and the correct gaskets?

is there anyway you can send pictures of the exhaust collers and the spacers. also silicon wont seal combustion pressure or gas it would just blow out. it sounds to me that you might have to loosen all the exhaust mount bolts so that you can shift things around. don't tighten anything until everything is in its proper place then tighten from the head out and work your way back from there.

Luke, somethings missing. I've seen 2 or 3 different header configurations. the most common have lips where header meets head. in this case, ex gasket fills head port and header seals to face. then a pair of 1/2 moon collets are secured via a 2 eared heat exchanger plate. on some racing applications flanges are fit to head, and headers fit over them and are secured via springs. Pic's would help. G

Assure the old exhaust gasket is removed. Sometimes there are two old gaskets in the same port where reassembled without new gaskets. The old gasket is often difficult to see all crusted inside the port.

Would always use new copper crush gaskets.

With exhaust clamps hanging loosely around header pipes and new copper gaskets fitted inside the head recesses (a dab of hi-temp sealant helps hold them in position), hold the headers in place on the head against the gaskets, and fit a pair of split collars onto each header pipe with the small non-flared ends of the split collars toward the engine to press against the flared ends of the header pipes. Use masking tape (or rubber bands) to hold the split collars in place during assembly. The flared ends of the split collars fit into recesses in the exhaust clamps. While holding everything in position, loosley start the clamp holder nuts onto the exhaust studs, and assure all parts being properly fitted and aligned before tightening the exhaust stud nuts against the collars.

The clamp will crack or break when tightened unless all parts are correctly fitted and aligned.

Clamps press against split collars.

Split collars press against header flanges.

Header flanges press against copper gaskets.

Good luck with the installation!

i am not formiliar with your setup,. but with a kz 900 , it is common to use thicker gasket o rings when u add a header. Kerker did not get the fit just right. Z1E has thicker gaskets for them or u can use 2.
Just a thought.

From kawasaki.com

[click on image to enlarge view]

Here's a link to Z1E listing for the oem copper gasket.

Click > Z1E copper exhaust gasket

Good Luck!

LukeJ wrote:

Hi guys, one issue I have been having is selecting suitable exhaust gaskets to fit between the engine and the headers.

I have a GPZ750A1 83 model.

I purchased a set of copper ones which fitted nicely over the end of the header pipes, but a not so subtle flash when I turned over the engine indicates I may have gotten it wrong.

Another thing is that the exhaust is a real pain to put on - there are I suppose brackets which hold the exhaust onto the engine, but inside these brackets there are like sleeves which seem to allow for a better fit - but don't really do the job all that well.

The whole thing seems a bit dodgy and Im not surprised at the results Ive been getting. I was thinking of using some hi-temp silicone or something to fill in the gaps.

I dont want to buy a new exhaust just yet, but I believe that will be on the cards eventually.

What tips does anyone have with fitting and exhaust and the correct gaskets?

luke,
you might have the wrong parts or assembled wrong..the gaskets dont go over the end of the pipes but rather butt up against the end of the
pipes inside the head and flatten when tightened
to create the seal.....the copper gaskets actually get placed in the head...i use the cheap-ass swamp yankee method and put a few good dabs of grease on the copper rings and that holds em in place as i put the header pipe up..burns off in a few after start-up.try to get one of two inside collars(flat flange out) started
and that will semi hold headpipe enough that you can get the other ones started....it aint fun but its doable...a second set of hands makes it a whole lot easier....good luck and let us know how you make out......keith

LukeJ wrote:

Hi guys, one issue I have been having is selecting suitable exhaust gaskets to fit between the engine and the headers.

I have a GPZ750A1 83 model.

I purchased a set of copper ones which fitted nicely over the end of the header pipes, but a not so subtle flash when I turned over the engine indicates I may have gotten it wrong.

Another thing is that the exhaust is a real pain to put on - there are I suppose brackets which hold the exhaust onto the engine, but inside these brackets there are like sleeves which seem to allow for a better fit - but don't really do the job all that well.

The whole thing seems a bit dodgy and Im not surprised at the results Ive been getting. I was thinking of using some hi-temp silicone or something to fill in the gaps.

I dont want to buy a new exhaust just yet, but I believe that will be on the cards eventually.

What tips does anyone have with fitting and exhaust and the correct gaskets?

I use the hollow copper donut gaskets. On one side, I have to use two gaskets to get it to seal. I crazy glue the two donuts together to keep them from slipping.

Silicone can NOT be used on an exhaust flange it will burn up.

After looking at the replies I have reinvestigated the issue and I'll be putting some pics up tonight.

One thing I noticed was that the split collars are fitting loosely on the flange of the gasket, even when the clamps are on as tight as they can go.

Under these conditions, the headers still have a bit of freedom - if you poke them with your finger they wobble a bit. Maybe these collars are slightly too large or not shaped correctly onto the flange of the headers.

Im going to try a couple of gaskets in one head as the left-most head has the most wobble.

Its a 4-1 system too. Photos coming soon

all most sounds like your split collers are on backwards they should have the little L shaped return on the side facing the nuts...two coppers or a new with the old and some grease dabs like keith said and you should be o.k...dont strip the exhuast studs or you will be sorry.....good luck let us know how you make out.....LukeJ wrote:

After looking at the replies I have reinvestigated the issue and I'll be putting some pics up tonight.

One thing I noticed was that the split collars are fitting loosely on the flange of the gasket, even when the clamps are on as tight as they can go.

Under these conditions, the headers still have a bit of freedom - if you poke them with your finger they wobble a bit. Maybe these collars are slightly too large or not shaped correctly onto the flange of the headers.

Im going to try a couple of gaskets in one head as the left-most head has the most wobble.

Its a 4-1 system too. Photos coming soon

LukeJ wrote:

...the split collars are fitting loosely on the flange of the gasket....

:huh: Uncertain what's going on here, but the split collars don't make any direct contact with the gasket.

As noted in the above posts, parts coming from the exhaust port are in this sequence:

Copper gasket;
Header flange;
Split collars;
Clamp.

Consider flange end of the header pipe, and that an oem (stock) header may or may not have a slightly thicker flange than the flange found on an aftermarket exhaust header.

Where the aftermarket header flange is thinner than on the oem pipe, more space exists between the exhaust clamp and flange. Thus a slightly longer split collar is often used to reduce the space. Thicker flange = shorter collar. Thinner flange = longer collar.

The several new and different brand aftermarket exhaust systems I've purchased all came supplied with new split collars of the correct length for the particular exhaust system involved.

So the split collars in this instance might for whatever reason be a little too short. But it's impossible to know absent initial correct assembly.

Would also carefully compare lengths of all existing collar halves to assure there're all exactly the same length. And that the flanged ends of the collar halves are not damaged and thereby unable to fit snugly into the clamp recesses.

Good Luck!