advice on rebuilding engine

[richard1705]

Ok so I've just been down to my mechanic who is a stag guy . It seems best way to go is to fully rebuild my engine using the rimmers rebuild kit . Which has everything in it .
Just your opinions on are these kits any good material used wise. Also I've noticed it comes with hardened crank which is about 1k . Is this a decent price for crank. Or can I save some money buy getting my crank machined separately.
Thoughts plz
Much appreciated
Rich

[mole42]

Beware of the kits - I'm currently having to rebuild the top of my engine because the head gaskets that they are selling are rubbish. I've no knowledge about any of the other parts.

[richard1705]

whats the better head gaskets these days

[mole42]

I've just bought a set from Robsport - they are the proper (SOCTFL-funded) BGA gaskets with the sealing bead around the edge. The inlet manifold gaskets look better than the Rimmers ones too. I'll be fitting the heads again over the weekend and filling the coolant system, so I'll let you know!

[richard1705]

Great thx
Good luck

[marshman]

I rebuilt my engine earlier this year. Just made a list of the bits I actually needed and bought most of them from Robsport. Gaskets were top quality. No issues since rebuild. I didn't do anything with the crank as it looked and measured up OK, I just fitted new shells to big ends and mains.

Problem with getting a complete kit is there will be quite a few bits you don't really need and some that you do will not be in it. Also you have little or no control over the actual make or quality of the individual parts. Ordered separately you know exactly what you are getting - e.g. Robsport confirmed the head gaskets were the SOCTFL sponsored BGA gaskets. A rebuild kit sounds nice in principle but bitter experience (not on with the Stag but on other classics) shows it not to be the case.

My 2p worth, no kit, order individual parts - I can recommend Robsport - been using them for years and as I said used them very recently for parts for my rebuild. Noi connection etc. apart from satisfied customer.

[mike@thenook]

+ 1 for Robsport, superb bunch of guys and their parts are top quality

[flying farmer]

As above. The Rimmers kits are cheap but the quality of some of the bits are lacking so I tend to order all the bits separately to ensure I get the best quality components, Robsport are good. When it comes to the crankshaft, they definitely need hardening after a regrind which is more expensive if you get your own done, BTDT
Neil

[Goldstar]

+ 1 for Robsport, superb bunch of guys and their parts are top quality

I ordered some bits from Robsport last Wednesday at 15:05 and got them at 1123 the next morning. Wayne is a star

[jbuckl]

Faversham are probably the most prolific stag engine rebuilders in the u.k.

However I’ve done a few over the years too.

Avoid rimmers if possible.

+1 for Robsport gaskets.

+ 1 for paddocks.

+1 for Ld part

+1 for Soc spares.

crank grinding & hardening maybe best undertaken at an engineering place nearby your location. None of our specialist suppliers do in house crankshaft repairs afaiaa.

a report on hardness, sizes & straightness is highly advised. Beware if those are not forthcoming.

Stag engine rebuilds do require some previous knowledge imho….

Without that there’s risks.

waterpump should have 1Nm torque to turn .

use a pioneer Weston seal and an rhp bearing.

other parts being offered can cause skew gear failure yuck and ££££

crank must be tuftrided.

conrods should be checked as per rom before reuse.
check little and big end for size & roundness; check for twist; crack test; check conrod bolts for bolt thread stretch. Consider little end bush replacement if worn slightly. Must be honed to size. Consider cleaning, shot peening and end to end balancing.
This level of conrod checking is often overlooked.

For a more fastidious rebuild a balance check of the crank, conrods and pistons, together with flywheel and front pulley can be undertaken.
This can result in a beautifully smooth stag engine… but it may add quite a bit of cost and isn’t essential.

oil pressure should be 47 psi (ish) on a newly built motor, more is not good. Lower within reason is not a big issue.

priming oil circuit before firing is mandatory to avoid early life wear. (3 minutes turning to prime is not unusual ) consider using a drill to prime )

king bearing shells do work.

aligning the timing chains & setting the tensioners needs to be done carefully.

it’s very easy to over tension, misalign & have early life wear.

some guides supplied (l.h.) do need fettling to fit & function correctly.

many schoolboy errors have been observed during strip down & eyebrows raised when seeing previous engine repair receipt sizes and origins.

recent example :- large amount of cam bearing bore damage caused and previously over looked.

damage possibly / probably caused by incorrect reassembly of cam caps. Head damage very expensive to correct subsequently. Some mis-matched caps had been used seemingly to cover up the situation. Yuck.

older example:- conrods inspected for straightness , bore roundness , size and twist.

3 crankshafts later one of the previously measured conrods was found to be twisted & out of round.

measurement was not reported…. Just verbally confirmed as being within specification , when it really wasn’t…. Respected conrod manufacturer had been used for inspection / measuring.

[richard1705]

thx for that . alot to think about . I think my mechanic which is an ex robsport mechanic
wants to take the easy way for ordering parts just in 1 go . thats why he recommended rimmers kit .I don't really have the knowledge as to what exactly I need .but saying that I will definitely phone around and try to avoid r
also the water pump is another big thing as I've heard new ones are cr.p

[mole42]

thx for that . alot to think about . I think my mechanic which is an ex robsport mechanic
wants to take the easy way for ordering parts just in 1 go . thats why he recommended rimmers kit .I

I don’t believe that there is an easy way with Stag engines. It’s a great engine if built properly, a source of disappointment and a money pit if not.

[richard1705]

the paddocks crankshaft looks good nitrided with bearings ect for 645.00

[richard1705]

also how about water pumps . New ones aren't any good .
I think what I'm trying to do is get the more important bits from reputable suppliers
or recommend by yourselfs .
then just use the rest of bits from the rebuild kit .
what do you reckon .

[Lingen]

I thought that the ones R.B. sell now are OK. A "Well known" Stag engine rebuilder has been using them for some time with no failures to date. Someone I know had the gear on the one he bought tested for correct hardness, and the result was good.
Just saying....
Mike.