Engine rebuilders - recommendations

[Ferds]

All,

it it looks like I'm going to need to get my engine rebuilt - as its using / burning oil now.
the oil pressure is good and the engine does run well, but over the years the oil consumption has steadily increased...

As a result I'm looking for recommendations and feedback (good or bad) - on people who can do this for me...

The usual suspects (in no particular order) are:-
Tony Hart / Enginuity
EJ Ward
Faversham Classics

Is there anyone else?

Thanks
Ferds

[Jeff]

Kryten.

[Motorsport Micky]

Might be worth trying some BMEP first, will take a few months to see if it gives a result, but lots cheaper and at least you can keep driving it.

Micky

[StagJonno]

Might be worth trying some BMEP first, will take a few months to see if it gives a result, but lots cheaper and at least you can keep driving it.

Micky

Is this a fuel or oil additive, Micky - not come accros this (except as brake mean effective pressure)?

Jonno

[nib]

Cambridge Rebores in Burwell, Cambs.

[richard1705]

+1 kryten

[mjheathcote]

If the oil pressure is good, seems a shame (and unnecessary expense) to fully rebuild.
Sounds like maybe a worn bore problem.
Have you done a compression check, and what are the plugs like?
Glaze busting and a new set of piston rings might all be necessary.
This is okay if doing yourself, but these days if entrusting to someone else, it is always a full rebuild job at £££

[Motorsport Micky]

Is this a fuel or oil additive, Micky - not come accros this (except as brake mean effective pressure)?

Jonno

Gold Star and a tick Jonno.

BMEP = "Brake Mean Effective Pressure" which paraphrases as "the rev range in an engine where it develops the highest compression and power throughout it's downward power stroke. This expands the piston rings bedding them into the cylinder walls and helping them develop their best seal.
Make no mistake "bedding" the piston rings on a microscopic level means forcing them into contact with the cylinder walls and "gouging" material from them (don't be alarmed, we are talking microns) in a fashion similar to having the bores honed, except without the cost !

It's not uncommon for cars used for fun or gently to suffer glazing on the cylinder bores, (try reading the Porsche forums, it's rife). Owners often think "I don't use the car gently ! I rev the nuts off ! " however revs are not what's required to keep the cylinder walls free from glaze. Using the car in it's torque range is what's required, and we aren't talking about trickling it along at about 50mph with 2000 revs on the clock, that's "easy footing" it and often causes glazing.

If your engine does suffer with glazed bores the piston rings haven't been expanding enough to keep a strong gas tight seal on the cylinder walls, either they are stuck or the use of the car hasn't been expanding the rings. On a rolling road it will take maybe 20 minutes of loading the engine (putting the engine under pressure or load at full throttle within it's torque range) to start removing the glaze and bed the rings in correctly. On the road you can do it by driving the car correctly, (assuming you haven't been driving it like this previously).
Find a road with a long uphill gradient (motorways are good for this) make sure you are in top gear and brake the speed dropping the revs down to about 800-1000 revs below where max torque is. This depends upon what cams you have fitted but we can assume the standard cams torque max is at about 3500revs. Then floor the throttle...and keep it there, when the car gets to max torque brake the speed down again to about 1000 revs below and give it the beans again, and again. When on top of the gradient come off at the next junction and return the same way using the other side of the motorway giving it the beans in the same fashion. I have a favourite section about 6 miles from home and try to use it about every 8 weeks or failing that whenever I'm out and circumstances allow I'll do the same on normal roads.
Modern cars and trucks with their "plateau honed" bores suffer from this even more than older vehicles. The plateau honing and general increase in quality in engineering standards from about 50 years ago mean machined surfaces become even more glass like and less likely to hold oil as required. Modern trucks aren't considered run in until about 60,000 mile on the clock (and that's hauling 44 tonnes) and obviously driving it within it's torque range) so glazing is to be avoided.

Worth trying before lashing out the money but remember this is a slow process, if you do this weekly don't expect results before the end of the summer which may fit in then with making a decision whether or not to "engineer" the problem out.

Micky

[StagJonno]

Gold Star and a tick Jonno.

BMEP = "Brake Mean Effective Pressure" which paraphrases as "the rev range in an engine where it develops the highest compression and power throughout it's downward power stroke. This expands the piston rings bedding them into the cylinder walls and helping them develop their best seal.
Make no mistake "bedding" the piston rings on a microscopic level means forcing them into contact with the piston walls and "gouging" material from them (don't be alarmed, we are talking microns) in a fashion similar to having the bores honed, except without the cost !

It's not uncommon for cars used for fun or gently to suffer glazing on the cylinder bores, (try reading the Porsche forums, it's rife). Owners often think "I don't use the car gently ! I rev the nuts off ! " however revs are not what's required to keep the cylinder walls free from glaze. Using the car in it's torque range is what's required, and we aren't talking about trickling it along at about 50mph with 2000 revs on the clock, that's "easy footing" it and often causes glazing.

If your engine does suffer with glazed bores the piston rings haven't been expanding enough to keep a strong gas tight seal on the cylinder walls, either they are stuck or the use of the car hasn't been expanding the rings. On a rolling road it will take maybe 20 minutes of loading the engine (putting the engine under pressure or load at full throttle within it's torque range) to start removing the glaze and bed the rings in correctly. On the road you can do it by driving the car correctly, (assuming you haven't been driving it like this previously).
Find a road with a long uphill gradient (motorways are good for this) make sure you are in top gear and brake the speed dropping the revs down to about 800-1000 revs below where max torque is. This depends upon what cams you have fitted but we can assume the standard cams torque max is at about 3500revs. Then floor the throttle...and keep it there, when the car gets to max torque brake the speed down again to about 1000 revs below and give it the beans again, and again. When on top of the gradient come off at the next junction and return the same way using the other side of the motorway giving it the beans in the same fashion. I have a favourite section about 6 miles from home and try to use it about every 8 weeks or failing that whenever I'm out and circumstances allow I'll do the same on normal roads.
Modern cars and trucks with their "plateau honed" bores suffer from this even more than older vehicles. The plateau honing and general increase in quality in engineering standards from about 50 years ago mean machined surfaces become even more glass like and less likely to hold oil as required. Modern trucks aren't considered run in until about 60,000 mile on the clock (and that's hauling 44 tonnes) and obviously driving it within it's torque range) so glazing is to be avoided.

Worth trying before lashing out the money but remember this is a slow process, if you do this weekly don't expect results before the end of the summer which may fit in then with making a decision whether or not to "engineer" the problem out.

Micky

Thanks for a very full explanation and reasoning, Micky. Applying this remedy sounds like fun . I haven't noticed any smoke when driving along, though I quickly get build-up of oily residues immediately above the exhaust pipes, so must build this corrective treatment into my driving - got some nice hilly sections on the A69 on the way to Newcastle (and back). Must say that my "normal" driving style doesn't take the engine to more than 3,500 rpm and achieving this in a much more gentle fashion (and doubt the immediate PO got it above 3,000 rpm).

Jonno