Advice on rebuilding a 1098

Post by **MikeNash** » Thu Jul 23, 2009 8:21 pm

Dear all,
My old 1963 Trav's got a Gold Seal engine put in about 1972 and is showing its age. I've done 57K in it and I believe the engine's done well over a 100K, and its probably unwise to tune this aging beast.
It goes well, will cruise happily all day at 65 (true) even with a small trailer and it returns 35+ mpg. However, I only get 300 miles to the pint of oil if I'm careful, and driven hard its down to 200. Oil pressure hot (210F) is 42 psi max and down to 8 psi on hot idle. The valves were checked when an unleaded head was fitted 13K miles ago and at the moment the compressions cold with the the throttle wide open are (front to back and the second figure with oil squirted thro' the plug holes) 162/178, 175/198, 172/181 and 168/175 psi.
The pistons are 20 thou oversize. I checked the bigends and the two front mains only 2k ago and they were within half a thou of ovality i.e. as near a round as you can measure from beneath with the crank installed, and they had no grooves.
The crank is 40 thou undersize. I replaced all the bearings but, of course, can't get at the rear bearing. I think it all has to come out with the g'box, clutch and flywheel off to get at this one Am I right?
A new oil pump would help too, I think.
I'm inclined to get it all out, fit a new crank, bearings, pump, etc and rebore. But would only a new pump and rear bearing sort it out?
But it goes so well, that perhaps I should buy another and build up separately.
What's your advice? Regards, MikeN.
(I'm off to Exeter tomorrow (240 miles round trip), so if you get passed by a quick Trav and trailer and sprayed with oil - its me!)

Post by **bmcecosse** » Thu Jul 23, 2009 9:13 pm

I would keep using it exactly as it is! The oil consumption is not THAT high - just use cheap ASDA 20W50 oil. Changing that rear main is not going to help the oil pressure all that much - and it's not disasterous at the moment anyway. It is engine out to get at the rear main and the oil pump. These compression figures are actually very good - I suggest making sure the breathers are clear and one of them is connected to the intake system - best at the carb rather than at the air filter. If there is a slight suction in the crankcase - it stops oil being forced up past the oil rings and being burned.
Meantime - keep an eye open for another engine - and overhaul it if it needs doing. But really - your engine has lots of life in it yet!

Post by **MikeNash** » Sun Jul 26, 2009 10:08 pm

Thanks for the encouragement Roy.
I think I'll follow your advice and keep it going while I look for another engine - and do a quck check on those breathers. (Missed a good one recently up your way - Jefftrav at Inverness.)
Regards, MikeN.

Post by **bmcecosse** » Sun Jul 26, 2009 10:10 pm

Well - Jeff is hardly 'up my way' - he's a long way north, although granted nearer me than you.

Post by **MikeNash** » Sun Aug 16, 2009 8:37 pm

Roy,
I've sent you a PM, MikeN.

Post by **bmcecosse** » Sun Aug 16, 2009 9:09 pm

Nothing there Mike !

Post by **MikeNash** » Sun Aug 16, 2009 9:40 pm

Roy,
Have despatched another PM. MikeN.

Post by **bmcecosse** » Sun Aug 16, 2009 9:42 pm

Deleted by bmc

Post by **MikeNash** » Sun Aug 16, 2009 9:50 pm

Roy,
E-mail sent. MikeN.