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Discussion Starter #1
Have had loss of power for a while no, especially under load, not all the time though.

Sometimes I can hardly get over 70!! Changed HT leads and plugs last week but no inprovement.

Have been searching around and it sounds like the Cat may have collapsed, blocking the exhaust.

Is there an easy way to check this withouth removing the cat? e.g. putitng my hands over exhaust or something?

If I remove the Cat, can I go for a drive without killing any old ladies with the noise
 

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Broon,

Does it rev past 5krpm in neutral?

If not then I recon your cam timing may be out (one tooth on the inlet cam).

Had a similar problem with Bob's old metty when she had that.
 

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have you got low compression, have you got a little crack or leak in the head gasket, just clutching at straws for you here though:s2h:
 

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It could well be your cat; a dying cat is often accompanied a load rattling sound. The only way of finding out is to take the cat off and visually inspect its innards, if it looks to failing you could gut your cat and replace it before the next MOT.
 

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Discussion Starter #5
lildemon said:
have you got low compression, have you got a little crack or leak in the head gasket, just clutching at straws for you here though:s2h:

Bloody hope not, I just got a new one in November :(
 

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Broon said:
Bloody hope not, I just got a new one in November :(
broon scratch that thought then, i did say i was clutching at straws m8, what about bits dropping into the pertrol because of the fuel filter, our car did that a few yrs ago
 

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Broon said:
If I remove the Cat, can I go for a drive without killing any old ladies with the noise
I think everyone South of the border could here you if you run it with the cat removed!!!...

When is your MOT due??......... De-cat pipes are only around £30 so you could remove the cat and fit one of these, this would prove if your cat was shot, but give you untill your MOT is due to get a new one!!..;)
 

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Discussion Starter #8
Chris T said:
It could well be your cat; a dying cat is often accompanied a load rattling sound. The only way of finding out is to take the cat off and visually inspect its innards, if it looks to failing you could gut your cat and replace it before the next MOT.

I ahve to admit since removing the sound deadening material at the weekend, I have noticed a very rattly noise coming from the engine bay, like there is a tin can half filled with screws and bolts, rattling about in the engine if you can guess what I mean? :lol:

Ironically I bought a de-cat pipe last week by mistake off ebay (how did I know it would go for 10 pounds !!). But it does not fit my F so I need an adapter and a MIL eliminator. still if my cat is knackered, I may just stick with that for the moment until my MOT comes up in Nov.

I have jujst ordered some cat saver nuts so I will remove the cat once they have arrived, if it is bust , then i will holow it out. If it is not bust, I will put it back on. I presume I can test drive it without the cat on? Its not going to put any hot gasses anywhere they should not be is it?
 

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The sound you describe could be a dead cat.

I wouldn’t start the engine without the cat or at lest a replacement pipe.:err:
 

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Discussion Starter #10
cjmillsnun said:
Broon,

Does it rev past 5krpm in neutral?

If not then I recon your cam timing may be out (one tooth on the inlet cam).

Had a similar problem with Bob's old metty when she had that.

Jesus, I cant keep up with all these replies. :lol:

I am pretty sure it is flatting out at around 5'ish revs whilst driving, but have not tried with it in neutral. will try tomorrow CJ, thanks.

It has been noticed since my HG was replaced so maybe the timing was not done right, but having said that, some days it just goes like a bullet, and others (more often) I feel like I am driving a 1.2, not a 1.8.

Always seems fine in 3rd too if that makes any sense, but 4th and 5th and even 2nd are not what they should be.
 

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Discussion Starter #11
lildemon said:
broon scratch that thought then, i did say i was clutching at straws m8, what about bits dropping into the pertrol because of the fuel filter, our car did that a few yrs ago

Mmm, thats an interesitng one too. It is one of the last things I have not changed this year :lol:. After my HG was replaced the helpful MGR dealer left me with no fuel (even though I new there was loads when I out her in) and I ran out of fuel on the way to the garage (and on my way to teaching a class of students). I kind of noticed the power loss around the same time and did bring it up in a thread opn here abo9ut the fuel being dirty after running out. Maybe this would explain the inconsistency.

However I would be inclined to go with Chris T and other on the cat thing due to the horrible noise the engine seems to be making. At least that would be a better explanation (financially) than something wrong wih the engine itself.

I am now convincing myself due to some older posts that you simply cannot fit a bypass to a MY2000> F and TF due to the extra bend. IS this right. I think the adapter pipe was actually for mark 1 Fs, not "mark 3"
 

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Discussion Starter #12
Mmm, one more question. When removing the cat and if the nuts are rusted on, do I simply need to cut the heads off the nuts (witha dremmel or something). i.e is it the nuts that rust on , rather than the bolts themselves
 

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Fuel filter?

The rattly cat is hardly the cause of your loss of power. It sounds more like loss of fuel supply. Have you changed your fuel filter recently?

Diagnosing a cat with a loose matrix: Knock on it with your fist. If the core is worn loose you should hear it rumble inside the can.
 

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Discussion Starter #14
jonaf said:
The rattly cat is hardly the cause of your loss of power. It sounds more like loss of fuel supply. Have you changed your fuel filter recently?

Diagnosing a cat with a loose matrix: Knock on it with your fist. If the core is worn loose you should hear it rumble inside the can.

There are loads of threads about loss of power which have been caused by a collapsed cat.

I will give the cat a bash tomorrow :lol:
 

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Hi Broon

Have not had time to read all on this but have you tried taking the air filter out of line & see what happens.

MikeS
 

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Discussion Starter #16 (Edited)
cjmillsnun said:
Broon,

Does it rev past 5krpm in neutral?

If not then I recon your cam timing may be out (one tooth on the inlet cam).

Had a similar problem with Bob's old metty when she had that.

I revved it this morning CJ and it went right up until it was limited, just over the first red line so at least thats one major thing ticked off.

Interestingly, this morning was one of her 'normal' days. Did not notice any power loss. Maybe she just likes the sun.

Have not had a chance to check the cat yet. Will do it tonight.

Why can I never just have a striaght forward problem.
 

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You will need a nut splitter if they are badly rusted, any good tool supplier should have them in stock and they are only a few pounds. Standard M10 nuts will fit the Cat threads.

Dont forget about the spare gaskets although the old ones can be re-used but you have to press out the recess again. A lip off an empty food can be used for this, can give you further details on this if you want.
 

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Discussion Starter #18
Thanks D.R.

I ahve orderd the CAT fitting kit (stainless bolts, gaskets etc) so that wont be necessary. I saw a nut splitter in the local autoparts store a few weeks back so may just get one on the way home, just in case.

Thanks.

MikeS I tried that a few wekes back and it seemd to help so I cleaned the filter, but I would not expect it to get that bad after only a few weeks of driving
 

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the only problem with using a nut splitter is that the nuts are splayed at the base, so this needs grinding off first so the splitter covers the full nut depth.
 

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Broon said:
I am now convincing myself due to some older posts that you simply cannot fit a bypass to a MY2000> F and TF due to the extra bend. IS this right. I think the adapter pipe was actually for mark 1 Fs, not "mark 3"
You can fit a bypass to an MY2000> F and TF. You either need a bypass pipe that has the bend incorporated into it, or a Mk1 bypass and an adaptor elbow (which will need a mounting boss for the CO2 sensor on it). Whichever you use you will need to use a MIL eliminator.

The cat has studs pressed into the flange. These then go thought the silencer/manifold flange and have a nut on the silencer/manifold side.
If you don’t need the cat you are taking off, you can simply grind straight through the nut and the stud.
But if you want to re-use the cat then you need to carefully grind just though the nut and leave the stud intact. If you damage or shear the stud you will need to drill it out and replace it with a bolt, which is very difficult as the heating/cooling of the exhausts system hardens the stud metal over time.

Unless your fitting a bypass or sports cat (which don’t have studs), then you wont need the bolts included in the fitting kit. You will only need the nuts and gaskets. If the gaskets in the fitting kit are made from a single layer, then consider refitting the old gaskets as the OEM ones are multi layered, and Pete & myself found these sealed a lot better than the single layer gasket when we fitted his silencer (when we used the single layer gasket it leaked).
 
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