engine Opinions sought: engine rebuild kits

[AndrewP]

Folks,

 

Just wanted to see if anyone on here has used the Rimmer Bros complete short or complete engine rebuild kits or kits (purchased as a single transaction) from the other suppliers?

 

Appreciate any comments good and bad as looking to rebuild the motor and a complete kit is a convenient (and cost effective) way of rebuilding with new oversized pistons, mains, big ends etc.

They appear to supply County brand pistons and brearings and opinion seems to be divided on their quality vs. cost.

 

Thanks for any feedback.

 

Andrew

[RogerH]

Hi Andrew,

the county piston and bearings V cost it excellent, top notch.

 

Their absolute quality compared to the very best is slightly lagging but only slightly.

 

But then a Jag is slightky behind a Ferrari

 

Roger

[tr graham]

depends on the model of ferrari !!! maybe a bit more than slightly

[pinky]

I wouldn't go to rimmers if it was Free

 

Chris witer, for engine kit, good advise, talks the talk

Edited November 4, 2016 by pinky

[Guest ntc]

The parts are fit for purpose but you get what you pay for,and the end of the day it is the person that fits them.

[DaveR]

Last time I did a 1500 Spit engine rebuild three/four years ago Rimmers had OE spec Big and Main bearings in stock as an option to the county brand. These were more expensive but that's what I bought. Its worth asking any supplier if they have OE spec components.

 

Dave

[astontr6]

Hi Andrew,

 

I have just rebuilt a 1973 TR6 Engine! The first thing that was pointed out to me by 2 well known engine restorers was that to re-build to modern standards, that after stripping down the engine, is to access exactly what the condition of the block, crankshaft, flywheel & con-rods etc. I ended up with re-bore, re- ground crank + balanced, re-faced & lighten flywheel + balanced, con-rods balanced to all the same weight at each end, County Pistons used but all balanced to same weight, whole of bottom end then balanced as an assembly, including clutch. It was pointed out to me that these engines are poorly balanced. For example my con-rods were miles out. Quote ' they always are!'

Chris Whitor oil pump used, as well as his valve springs TR5 type with Newman fast road cam and Newman's EN40B cam followers. Over, the last 10 years there seems to have been a lot of problems with camshafts and followers, wearing out within 5K miles, so I took their advice. Their policy was to use the lightest valve spring rate that you can get away with.

Lastly it is very important to access the wear on the camshaft block bearings as they have a major effect on oil pressure, I was lucky that mine were within tolerance as this is an expensive job to line bore and use Spitfire shell bearings.

 

So far I am very pleased with the result. The engine pick up is much quicker and runs really smooth.

 

Bruce.

[Mk1PI]

I think Bruce sums it up - use the major parts like Pistons from Rimmers but look into other suppliers for things like Cam followers / cams if required. Beware some new spares which seem very weak if not NOS - chain tensioners being too soft and chains being too short springs to mind. I have heaps of NOS Payen ancillary gaskets - even a few headgaskets - available in exchange for a six pack.

Oil pumps are often absolutely fine and in better condition than new ones if measured.

[Andy Moltu]

Unless building a highly tuned engine County should be fine. If you are building a screamer then you'd probably be looking for forged pistons and OEM shell bearings.

[AndrewP]

Thanks gents,

 

I`ll take peoples advise and give the kits a miss as it seems like I may end up throwing some bits away and/or paying more if some of the parts self destruct whilst running.

 

Seems the best way is to selectively get the best I can buy for the money and take a close look at the OEM/original stuff before I rush out and buy everything new.

The engine as it stands has good compression, had good oil pressure and no known issues so it may be that I can re-use cam, followers etc etc.

 

I`ll tear the engine down in the next week or so and give everything a good clean out and assess what I have.

At minimum though I will get a re-bore (due to the bore damage) and depending on the crank condition, will put a set of mains, big ends and thrust bearing(s) in it for peace of mind.

 

Thanks for all the advise..very much appreciated.

Cheers

Andrew

[AndrewP]

Looks like the bottom end and big ends are all in very good condition.

 

Looks also like someone has been (at least the bottom end) here before (Vandervell big ends, but another make mains)

 

[astontr6]

Andrew,

 

When you check the cam followers, look at the bases to see if there is any sign 'black dots' in this area. If there is, the surface hardening is starting to break up, bin them! The cam followers are a major failure point on this engine and then they destroy the cam lobes. Lastly do not use valve springs heavier than TR5 for road use as this aggravates the problem, also check the cam shaft bearings in block, for wear. Especially on the cam wheel/chain end.

 

Bruce.

[Nick Jones]

Andrew,

 

When you check the cam followers, look at the bases to see if there is any sign 'black dots' in this area. If there is, the surface hardening is starting to break up, bin them! The cam followers are a major failure point on this engine and then they destroy the cam lobes. Lastly do not use valve springs heavier than TR5 for road use as this aggravates the problem, also check the cam shaft bearings in block, for wear. Especially on the cam wheel/chain end.

 

Bruce.

This is true. Front and rears ones tend to die first for some reason. If re-using the followers and cam, the followers need to go back in the same location.

 

Check any new followers for flatness on the cam face by placing two face to face. There should be no rock whatsoever. There are still some suppliers out there who think the followers should be crowned.

 

Nick

[Graze]

Andrew

 

I think it's worth replacing cam followers with the best you can get - they are cheap!

 

My rebuilt TR4 engine destroyed itself due to cam followers failing (one exploded and jammed the cam at about 4500 revs)

 

I think the valve springs were way over rated contibuting to the problem

 

Graeme

[TriumphV8]

There is a general opinion to make springs too hard.

As people can not check if power is sufficient they

often think the harder the better.

 

Unfortunately the next worse thing is that we idle the engines

much more than in earlier days or when used as sports cars.

 

Both make the things even worse when combined.

Its not that the systen fails from high revs, it is that the

parts already suffered before and got bad surfaces

and/or bad shape. That lets them fail at next reving high.

 

In reality we often take cams with more lift what rises valve

spring forces very much. I had a four valve engine years ago

that was limited to 6000ropm and after tuning I had to lower the

springs for the cam and with the hot cam and much less spring

force at closed valves it was able to rev up to 8000 without trouble.

 

So many many broken valve trains I inspected have been more a

bad combination of parts than bad parts itself.

With no doubt our parts are not the best and the factory who builds

them together will blame the quality but often its not the main reason.

 

We have to take better care on the weakest parts we have and less

claim for better parts than can withstand the wrong mounting.