Poor acceleration above 30mph + gravelly engine sound

[mattinhertford]

Hi all,

Symptoms are pretty much as per the subject heading. It reaches around 30mph OK, but then when i apply more acceleration to go faster, it does go a bit faster but there is an accompanying noisy gravel type sound from the engine. Seems like pressing the accerator results in more engine noise but no power to match it.

Has anyone had anything similar, any ideas?

Thanks

Matt

[bmcecosse]

We need more info - what size engine? Has it always behaved like this - or has this suddenly happened...or just got steadily worse? Is the sump oil level up to the mark? Does the oil warning light come on...when idling/when running?

[mattinhertford]

Hi, yes sorry, more detail....

1098 engine, oil level good.

Not had car long so not sure if it did this before, previous owner is now overseas so can't ask them.

Yes, oil light comes on.

Matt

[bmcecosse]

Hmm - oil light suggests low pressure and the noise suggests seriously damaged crankshaft bearings - or even a broken crankshaft. You could fit an oil pressure gauge to find out just how low.... - but frankly for all the time it takes - I would drop the sump and have a look at the big-ends - and the centre main to assess the damage...

[Chipper]

Alternatively, drain the engine oil into a suitable clean pan then pour the bulk of it into a spare can, and look for metal fragments/brass coloured bits in the residue. That would indicate bearing break-up.

[les]

Clutch on the way out?

[aupickup]

agree with les that is a possibility

[mattinhertford]

Thanks everyone. I hope it's something fairly simple like the clutch, not the crankshaft!!!

An expert is going to look at it next Monday, so I'll let you know what they say.

[bmcecosse]

Indeed could be slipping clutch - IF the engine revs up when you accelerate without the car getting any faster.... But the oil light tells a different story really. Simple test for clutch - car parked in open space - handbrake ON, select top gear - rev up really high and lift your foot straight off the clutch...... It should stall pretty much right away - if it keeps running...then the clutch is knackered. Hard to tell from your gravely noise - and you don't say if sudden - or gradual onset - but it could be a blown head gasket if it came on suddenly...... Who is the 'expert' ??

[mattinhertford]

The expert is a guy who owns a garage near me. Its a small independent that's been at that site for 50 years and he has an excellent reputation locally. He does a lot of classic car servicing. Not the cheapest but you know you're getting knowledgeable service. He's also offered me a deal on labour charges if I go and assist him (the Moggy is being serviced, and I'll be getting his advice on the 'problem' at the same time) as he knows I want to learn how to do it myself for future years, so I think I should be OK. A bit of money up front should a) put the car in the best possible nick now (since I don't know when it last had oil/filters changed etc), and b) set me up with the knowledge to do it myself in future years.

Just booked it for 2 weeks time so I'll let you know what we discover.

And thanks for all the tips/advice, really is a great community of people on here.

Matt

[bmcecosse]

2 weeks time?? You need that engine looking at RIGHT NOW. If it has run the bearings or blown a head gasket -= you need to NOT run it again till it's fixed. Surely he can spare you 5 minutes to check it over.... The overall idea of working with him sounds fine - although I suspect you will just be 'holding spanners' .......

[mattinhertford]

Not to worry, the car isn't moving until its been looked at. It's not my daily driver, just a hobby car.

Matt

[bmcecosse]

Aye - but 2 weeks....surely 5 minutes for a 'quick look' is possible?

[mattinhertford]

So, had the car checked over today, did some basic servicing (with help) too. Need to replace the front brake drums and cylinders which I reckon I can do myself.

Ref the problem described in the subject heading, the local garage reckoned it needs a new clutch but in terms of the bigger knocking/gravelly sound he reckons its something big like the crankshaft bearings, but says that if I was to put it to a proper garage to do then for all the labour costs that would come with an engine removal/strip down and repair, that its easier just to put in a reconditioned engine instead. He's going to cost it for me but said to expect £1000+ (includes cost of engine).

I've done some reading up about crankshaft bearings and for a novice like me i think its way out of my skills base. I've a gated driveway but no garage or lifting gear etc so I think its beyond me! However, i'm not really after paying £1000+ on top of the recent cost of buying the car so I've spent the afternoon with a cloud over my head trying to work out my plan of action.

The dilemma is that i couldn't sell it on, in good consciousness, because i couldn't do that to the next poor unsuspecting fellow, and i would probably lose a load of money straight away not getting what i paid for it.

The bodywork is OK, not mint, but certainly nothing major, i've stopped all the rust and it will need about 3 small patches welded into the floor/arches at some point in the future, but by no means urgently.

The guy warned me that I could end up spending more than its worth but I'm stuck for a solution. Could a 'novice' do the big engine removal/strip down?? Thoughts? Guidance? Sympathy!?!

[mattinhertford]

Getting on with the brakes anyway![frame][/frame]

[bmcecosse]

It's not a big overhaul - in fact it's very easy.. You don't need lifting gear to take the engine out - and an exchange crankshaft is less than £100 (plus carriage unless you can collect). You would need a new oil pump too, and a few gaskets. It's an EASY week-end job. Perhaps someone near you would be willing to lend a hand? But for that to work -we need to know where you are......

[mattinhertford]

Hertford town, Hertfordshire.

[bmcecosse]

A tad too far from me - but I'm sure there will be willing Minor owners near you to help on the job!

[les]

Once you've done the brakes and stuff it would not be unreasonable to tackle the engine, a manual would be very helpful and here you would get help, it would save you some money but there would be expense involved with the parts, you may well be able to buy another used engine but this has it's risks. I don't think it's fair to say the job is easy for a novice, I would say it's not, because you will need to determine if other parts need renewing while you're at it, and may not be familiar with the internals but taking your time and being methodical you would get some satisfaction when done. You will have to balance the options.

[bmcecosse]

It's just a case of unscrewing some parts - removing the old crank, fitting the exchange crank and doing up the bolts again.. ie there is no delicate 'fitting' - anything like that. But I agree - someone who has done it before would be of great assistance.