Poor running above 3000 RPM - Update

Jan 19th, 2003, 16:51

I thought I would post a quick update after all your good ideas - thanks for those. The sad outcome is that the CAT has melted down. I eventually put a pressure gauge on the exhaust where there is a blank plug opposite the Lambda sensor. I then started the engine and gently reved it up. By 3000 rpm, the back pressure was around 25-30 psi. I had done some research and found one web site (eurocats.co.uk) which said a maximum back pressure of a 3-4 psi was normal.

Today I removed the cat and with the aid of a small mirror was able to look at the inlet side and saw the face was melted over some 70-80% of its area. the outlet side was still a lovely shiney silver matrix - so there we go. I did change plug leads, distributer cap, rotor arm etc which all needed to be done. Just the timing belt to do next w/e.

Can anyone recommend a supplier for cats, or have any ideas on why this should have melted down. The (useless) Haynes manual indicates that tow starting, etc could flood the cat with petrol and then once started it may overheat. Have any of you experienced this? Any thoughts will be greatly received.

In the mean time thanks again. I will keep any eye on this site and maybe I will be able to help someone!

Cheers

Neil

Chris_Rogers · Jan 19th, 2003, 20:42

Could try: bba-reman.com or breakers.

I would try knocking the blocked part out of it and then see if you can still pass emissions, nothing to loose!

Jan 21st, 2003, 19:54

Hi Chris,

I took you up on your suggestion last night and cut the CAT on the inlet side. Totally glazed over, nearer 90%. The CAT is actually 3 individual sections so I was able to break out the first section of ceramic honeycomb and then weld the shell back together. Car goes like a rocket now. Pulls cleanly up to 6500 rpm etc.

New CAT arrives on Thursday. Best price was cats-direct.com at £206.00 inc VAT. Partco quoted £347.00 for the same 'eurocat' replacement. My local auto factors could then get this down to £307.00 so there we have it, assuming it turns up, cats-direct.com won hands down. I have received a call to say it has been dispatched, so fingers crossed. I will stick with the old one for a while to see if there are any underlying problems, but on the whole a very satifying evening - do you think the MOT man will spot the mig weld around it!?

Cheers

Neil

Chris_Rogers · Jan 21st, 2003, 20:29

Glad you had a success, at least you know your new CAT should solve the problem.

Jan 19th, 2003, 16:51	#1
neil.mackinlay Guest Location:	Poor running above 3000 RPM - Update I thought I would post a quick update after all your good ideas - thanks for those. The sad outcome is that the CAT has melted down. I eventually put a pressure gauge on the exhaust where there is a blank plug opposite the Lambda sensor. I then started the engine and gently reved it up. By 3000 rpm, the back pressure was around 25-30 psi. I had done some research and found one web site (eurocats.co.uk) which said a maximum back pressure of a 3-4 psi was normal. Today I removed the cat and with the aid of a small mirror was able to look at the inlet side and saw the face was melted over some 70-80% of its area. the outlet side was still a lovely shiney silver matrix - so there we go. I did change plug leads, distributer cap, rotor arm etc which all needed to be done. Just the timing belt to do next w/e. Can anyone recommend a supplier for cats, or have any ideas on why this should have melted down. The (useless) Haynes manual indicates that tow starting, etc could flood the cat with petrol and then once started it may overheat. Have any of you experienced this? Any thoughts will be greatly received. In the mean time thanks again. I will keep any eye on this site and maybe I will be able to help someone! Cheers Neil

Jan 19th, 2003, 20:42	#2
Chris_Rogers VOC Member Last Online: Apr 10th, 2017 16:55 Join Date: Jan 1970 Location: South Kent Coast	RE: Poor running above 3000 RPM - Update Could try: bba-reman.com or breakers. I would try knocking the blocked part out of it and then see if you can still pass emissions, nothing to loose!

Jan 21st, 2003, 19:54	#3
neil.mackinlay Guest Location:	RE: Poor running above 3000 RPM - Update Hi Chris, I took you up on your suggestion last night and cut the CAT on the inlet side. Totally glazed over, nearer 90%. The CAT is actually 3 individual sections so I was able to break out the first section of ceramic honeycomb and then weld the shell back together. Car goes like a rocket now. Pulls cleanly up to 6500 rpm etc. New CAT arrives on Thursday. Best price was cats-direct.com at £206.00 inc VAT. Partco quoted £347.00 for the same 'eurocat' replacement. My local auto factors could then get this down to £307.00 so there we have it, assuming it turns up, cats-direct.com won hands down. I have received a call to say it has been dispatched, so fingers crossed. I will stick with the old one for a while to see if there are any underlying problems, but on the whole a very satifying evening - do you think the MOT man will spot the mig weld around it!? Cheers Neil

Jan 21st, 2003, 20:29	#4
Chris_Rogers VOC Member Last Online: Apr 10th, 2017 16:55 Join Date: Jan 1970 Location: South Kent Coast	RE: Poor running above 3000 RPM - Update Glad you had a success, at least you know your new CAT should solve the problem.

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