MR2 Roadster Owners Club

The Workshop => General => Topic started by: Tom1 on February 15, 2025, 12:16

Title: 2004 roadster engine smoking
Post by: Tom1 on February 15, 2025, 12:16
Hi all.
I'd appreciate some guidance on an issue with my 2004 roadster.
It has been sat a good while and when it went for its MOT it wouldn't pass emissions.
I've used it a bit to try and clear it out but the engine is smoking excessively.
I've been advised it's a piston ring that is stuck and also there is a rattle when warm.
Is there anyone that can rebuild these engines?
Don't really want to buy a second hand engine that could have the same issue, or is this a rare problem?
Any advice greatly appreciated!
Title: Re: 2004 roadster engine smoking
Post by: Carolyn on February 15, 2025, 12:32
A decent rebuild will cost around £400 in parts and £1,000 on labour.  There are plenty of people who can do the job.  If you can take the engine out your self (and put it back in) you'll save around £500.

I used to do these quite regularly but I'm no longer up for the hard physical work of removal and installation.  Like many others, I'd consider the job engine delivered to me.

I think you could get a decent used one from our breaker (J-Spec) but you won't save much money as the cost of the engine will be similar to the cost of a rebuild.

The issue is not that common but not rare either.
Title: Re: 2004 roadster engine smoking
Post by: Gaz mr-s on February 15, 2025, 13:15
PM'd
Title: Re: 2004 roadster engine smoking
Post by: Pete McCue on February 16, 2025, 09:10
I read about the piston ring issues on these engines but I thought they'd sorted it by 2004 no?
Do the rings just get gummed up? If so, is there not anything that can be poured in the bores to dissolve said gum and free the rings? Like we used to do years ago with Reddex!  :))
Title: Re: 2004 roadster engine smoking
Post by: Carolyn on February 16, 2025, 09:13
Quote from: Pete McCue on February 16, 2025, 09:10I read about the piston ring issues on these engines but I thought they'd sorted it by 2004 no?
Do the rings just get gummed up? If so, is there not anything that can be poured in the bores to dissolve said gum and free the rings? Like we used to do years ago with Reddex!  :))

Yes the oil control rings get gummed up if oil is not changed regularly.

Nothing was sorted until the very last few cars, as the piston revision really didn't work. 

No amount of lotions and potions will free them up, I'm afraid, the pistons have to come out to be properly cleaned.