Dismantled the plenum chamber on the P38 and found a bit of wear in the spindle. I'm not sure how much movement is acceptable but having spoken to SC parts and Gower and Lee they don't have any parts anyway. Does anyone know of a source or how much play in the spindle is OK?
There's always a little bit of movement in them but you can get new bushes and seals. Bush part number is ERR1756 (£6.78 each from LRDirect) and the seals are AUD3577 (£3.90 each from Rimmer Bros) but I can't find anyone that stocks both so you are looking at two lots of postage. For parts your best bets are LRDirect, Island 4x4 and Rimmer Bros. Rimmers tend to be slightly more expensive than the others but if you are in a hurry their next day delivery really is next day.
Thanks Richard,
I'm guessing I need a new spindle as well, ERR4225, which Rimmers say is superseded. Is changing the bushes a big deal?
On a different subject do you know what the original spec for the tyres was?
Many thanks.
David
I think the hardest part is getting the screws out that hold the butterfly in place, I've never attempted it myself. Looked at it once and chickened out so decided the play wasn't something I would worry about. The idle control valve will adjust to compensate for any excess air that gets through. I noticed that Rimmers say that the spindle is superseded but they don't say to what and Microcat says that it is also supplied as part of a kit (along with the bushes and seals) but nowhere can I find the part number of the kit.
Original tyres were either Pirelli Scorpion, Michelin or Goodyear. Sizes were 235/70x16 if equipped with 7Jx16 wheels, 255/65x16 if 8Jx16 wheels and 255/55x18 if fitted with 8Jx18 wheels. All were 109 load rating and HR speed rating. The closest you are going to find in appearance to original are going to be Goodyear Wrangler HP All Weather. I had a set on mine up until last year, not bad but not brilliant in the wet, too road tyre for mud and absolutely useless on snow.
As always you are a fount of knowledge.
I might follow your lead and just accept a bit of air leakage. I couldn't find the kit part number either.
Thank you Richard
Not done an injection throttle body but have fixed a few carburettors over the years. As Richard said getting the butterfly screws out is a right pain. especially if no parts are available so the old spindle has to be reused after machining down restoring it to truly round for new bushes or sleeving the worn spindle. As I recall it spindle usually shows more wear than body on carbs. Main issue seems to be the force from return springs et al wearing things oval so the spindle is turning lopsided. On a modern injection system the idle system should compensate just fine until wear reaches lunatic levels. Carbs are lots more sensitive if you want half decent idle and low throttle behaviour.
Also need to be very sure that the butterfly screws are going to say put when you put it back together. A fully floating butterfly sans screws tends to have "interesting" effects!
Sort of work I've not done for a fair number of years now. Finally got old and wise enough to turn down (some) major grief jobs!
Clive
It was more a case of where the screws would end up if they came out that bothered me. They may be small and made of brass but I didn't fancy the idea of them getting sucked into the intake and finding their way into a combustion chamber.
I know of a couple of Nissan Elgrand engines that ate little steel screws that hold plenum flaps in place (flaps that alter airflow route in plenum, short route for high rpm, longer route for low rpm torque).. Six flaps on the V6 engine one for each cylinder (port runner in plenum), each flap is like a little throttle butterfly but performs the different function. One engine was destroyed, another ate the screws but seemed unaffected - I found the loose butterfly, it must have somehow gone against airflow direction and uphill in the plenum to come to rest on top of another butterfly for a different cylinder. Owner had me removed them all to prevent the same happening again, couldn't tell any difference driving the car afterwards but it'd probably be a couple of ft/lbs down on torque at low rpm. The flaps would be too wide to make it as far as the valves but the screws...
Sorry to bring other marques into discussion again, almost on topic though!
Lpgc wrote:
I know of a couple of Nissan Elgrand engines that ate little steel screws that hold plenum flaps in place (flaps that alter airflow route in plenum, short route for high rpm, longer route for low rpm torque).. Six flaps on the V6 engine one for each cylinder (port runner in plenum), each flap is like a little throttle butterfly but performs the different function. One engine was destroyed, another ate the screws but seemed unaffected - I found the loose butterfly, it must have somehow gone against airflow direction and uphill in the plenum to come to rest on top of another butterfly for a different cylinder. Owner had me removed them all to prevent the same happening again, couldn't tell any difference driving the car afterwards but it'd probably be a couple of ft/lbs down on torque at low rpm. The flaps would be too wide to make it as far as the valves but the screws...
Sorry to bring other marques into discussion again, almost on topic though!
My ST170 had variable length intake runners too. You could really tell the difference when the control mechanism for it died and stopped working. It lost almost all of its low down torque.
It worked differently on that though, from what I can tell. IIRC it had some kind of rotating mechanism controlled by a box of electronics (the IMRC) rather than butterfly valves. When the engine exceeded a certain RPM the IMRC moved the bit in the intake manifold that lengthened the runners.
Don't forget the swirl flaps on BMW diesels that saved the planet by lowering carbon emissions by hurling themselves into the combustion chambers of otherwise perfectly serviceable engines. (if you're kinky for diesels).
Thanks everyone for the thoughts. Enough to scare me off so will just go with it as it is.
Picked up a door and some wheel arch protectors today so happy days.
Looking at home Nickel plating some bits. I know it's off topic; will re-post if successful.
Thanks again
Wheel arch protectors? I thought you wanted to restore it to original not make it look like a Discovery.
Off topic isn't an issue on this forum, we normally get back on topic eventually unless the original question has been answered then it can wander off anywhere.
Don't worry Richard - just the standard original bits that go under the wheel arches.
Ahh, the inner wheelarch liners, that's OK then. You'll need some of these then https://www.lrdirect.com/ANR2224-Fastener/