full engine rebuild? or partial? Thoughts please!

[rockrockmcrock]

So my Spitfire IV (1500) has sat for 7 years (I had kids!) but the resto has finally happened. I've now completed the bodywork and moved to the engine. The bonnet is off, so access is easy.

The original plan was for a full engine rebuild (head, bearings etc.) - I've done it a number of times, last time was in the late 90s. Now I'm wondering if I shouldn't just leave the engine in the car and do a partial rebuild (head, front seal, oil pump) and hope I get away with the dry rear seal. But then there's the O/D and gearbox too... and the bonnet is off so removing the lump is easy at present.

So I'm in two minds - Should I pull the engine and gearbox for inspection?

Any thoughts guys? What would you rebuild/inspect and what would you leave alone after 7 years of standing in a dry garage?

[don cook1]

What was it running like before? If it was fine then perhaps I'd just change the oils, filters, flush the cooling system and perhaps a rebuild kit for the carbs. Petrol tank and lines might need attention.

If you take the head off you will refurbish it, then you will peer down the bores...new rings...advice on here is to get the bores honed for new rings...might as well get new pistons and a rebore, while the crank is off.....you get the picture.


Not broke then don't fix it!???

[rockrockmcrock]

Car was running fine up until a suspected minor head gasket failure (clouds of white smoke) on the way to work 7 years ago - so off the road it came right at the wrong time  :'(

Spot on about the way rebuilds usually go, I spent far too much time and money in the past that way - which is why I'm resisting or at least trying to be objective about it ;)

The good news is that I know a lot about this car as I've partially and fully rebuilt it many times since the early 90s. So as to what needs to be done this time:

Head: The heads off anyway and at the workshop - suspected head gasket failure and an old leaded head make a head rebuild for unleaded a no-brainer. Especially as the last time it was off in the late 90s, I only just got away without new valves (I was a student back then so cash was limited!)

Oil pump again I should have refurbed the last time around, but cash was limited. No brainer this time around really, although it was fine right for years after the late 90s rebuild.

Front crank seal This was starting to leak a little when the car came off the road

All the above are engine in repairs so I am starting to wonder if I forget pulling the engine/box - if it comes out I know I'm going to go the whole hog as those BE bearings were replaced last in the 90s so I may as well....and then there's the crank which was at it's regrind limit last time around....etc etc.

[DougBGT6]

Agree with Mr Cook, if it aint broke don't fix it! Groundswell of opinion is the memory of lead is good enough for an unleaded head so why do it? If your worried use the additives. Finally, it leaks, that's how you know it's a Triumph! ;D

[rockrockmcrock]

9077 wrote:

Groundswell of opinion is the memory of lead is good enough for an unleaded head so why do it? If your worried use the additives.

Yup, perfectly true from my experience - I've run on unleaded for ages relying on lead memory without issues. However, the valve seats were very pitted last time they were off and really should have been reground. Hence if I'm doing the head gasket I may as well have new valves and the valve seats reground, and if I'm having that, then I may as well have hardened seats put in at the same time.

TBH I'm astounded at the price at my local - £200 for seats, regrind, skim and all parts! I've used these guys for decades and they really know there stuff, so given some of the prices I'd seen around I'd expected it to be much more as they are real perfectionists.

[thescrapman]

10126 wrote:

Oil pump again I should have refurbed the last time around, but cash was limited. No brainer this time around really, although it was fine right for years after the late 90s rebuild.

Check carefully that a new pump is likely to actually be better than your existing one. New ones sometimes need work to bring them into spec.

[rockrockmcrock]

thescrapman wrote:

Check carefully that a new pump is likely to actually be better than your existing one. New ones sometimes need work to bring them into spec.

That's not good news as I'm pretty certain it'll be beyond the tolerances now  :-/

If I do need a new pump, who do you recommend I get one from? I was just going to replace the sator/rotor assay...

[nang]

I'd check the clearances against the specs first. I've got my 2500 in bits at the moment.......no white metal left on mains and big ends. Oil pump checks out ok. Just faced the cap and body with a bit of wet and dry paper on a glass sheet....I'd rather keep the original than an after market one. Bores are good so a hone, new rings and bearings and a shaft grind should do me. (I hope ) (dizzy)
Tony.