Dexta engine repair kits?

[Dextrous]

Anybody bought and used any of these? I know they can't be beaten on price however I've heard a few tails about quality and after sales service. I'm just about to find out if I need one for my NP Super.

Can you let me know your experiences? If it's a bit sensitive vendor experience wise then PM me

I'm guessing if Sparex do a kit then this would be good quality, I only hear good things from the trade about Sparex.

Cheers
Andy

[russelm]

I used one for my rebuild and found it good quality and had no problems, my machinest commented on the quality to (as he fitted and bored to size the new liners)

[Dextrous]

Thanks Russel

I'm guessing this was a Sparex kit?

I'm a bit confused about the need to machine the liner. Some kits say finished, some kits say unfinished, The Sparex kit for my super seems to be S.66597 and says "parallel semi-finished liner" I'm guessing that all liners will need a bit of work on the outside to make them fit the block?

When you buy a kit from a retailer it typically doesn't say which make it is, looks like I need to ask as there is a huge range of priced from £160 to £300 +VAT and there is no guarantee that the dearest is the best.

Cheers
Andy

[Tubal Cain]

The reason for boring the liners true after they are fitted is probably due to the fact that being thin walled and an interference fit they will distort when pressed into the block!

Gerald

[Dextrous]

Thanks Gerald, that makes sense. For a moment I thought that the external dimensions of the liner needed machining to match the block.

Cheers
Andy

[russelm]

I got my kit from Emmark but it did not have the valve bits (as I had a new head due to the original being cracked it was not needed).

As already said, a finished liner is no good on the Dexta engine as its not a drop in unit, its an interference fit so distorts during assembly requiring boring and honing.

[Dextrous]

Thanks Russel

That clears that up, if it needs it I think I will take the engine here to get the liners pressed in and bored/honed. While they are at it I'll get anything else that needs doing such as crank grind, valve seat lapping etc. Dunlop are selling the sparex kit at £191 + VAT. Add to that machining costs and any shell bearing and I guess it will come out around £500 or so.

Should I replace the core plugs while its out?

While I'm at it should I get a stage 2 cam installed and the head gas flowed and ported and a performance exhaust fitted Only joking, I did that to my old MG midget, went like a rocket afterwards.

Regards
Andy

[russelm]

I was with you all the way until you said about an A series which went well! (without fitting a BMW motorcycle head)

As a guide, I had the crank ground, liners fitted, bored and honed plus I got the machine shop to supply the main and crank bearings, this cost me just under £280ish from memory. I had a further quote at around £350.

You should be able to do the head yourself as valve lapping, checking and assembly is nice and easy.

[Dextrous]

Thanks Russel

I'll steal my dads valve grinding paste, I think he's finished his velocette venom renovation so won't miss it

Cheers
Andy