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Re: Spirit ?
PostPosted:Mon Sep 14, 2015 12:28 pm
Thanks Mike, sorry about the delay in replying, I have that problem too (quart into pint pot, springs to mind!!).
Love the video, thanks for that.
I kinda figured as much, yes the clutch does hook up instantly now so I'll probably take some out as it starts to bite if I rev it really hard when stationary.
lots to do over the winter, ready for next year.
Re: Spirit ?
PostPosted:Wed Nov 18, 2015 7:44 pm
Finally found some time to getr down to RDR HQ in deepest Kent & start investigating the various issues that we found this year. First to do was a leakdown test on the engine to see if we could find what was causing the excessive oil venting into the catch can. After taking out the plugs I found one possible clue as you may tell from this pic? Left to right is cylinders 1 to 4.
Next we did the leakdown tests & disovered a probable blown head gasket between cylinders 2 & 3 , confirmed by the above pic, I think! There was also seemed to be more air leaking past the rings & creating excessive crankcase pressure, so the decision was made to pull the engine for a teardown as it would be easier to do out & also make getting the trans out a lot easier, if not essential!!
After a lot of trial & error we finally removed enough peripheral stuff to enable the engine/trans to be pulled out in one go.
Now it was out, we could set about splitting the two & after a bit of faffing about removing even more bits of throttle linkage, we managed to get the trans & clutch can off. Taking the clutch apart it all seems good in there & was interesting to examine. After finally getting the starter motor off (it seems to be the first & last thing), we got the motor plate off & got the motor settled down on the ground. As the day was rapidly going by we tried to get the engine mounted on an engine stand but because it's such a tiny one (the engine!) it wouldn't fit any combination of arms & the protruding cover for the end of the camshaft also got in the way rather. So we decided to store it away until Dave can find time to make up some sort of adaptors to mount it. One interesting thing we discovered was the motor plate had a gasket seal on the back around the cam area.
As I wanted to see inside the trans, we mounted it on the engine stand & drained the oil out into a humungeous drain tray Dave had (thanks Bob!) & turned the trans over & removed the sump, revealing what we believe to be the cause of the gear selection issues!! See if you can spot it?
Maybe this one is clearer?
As was suggested by Mike Tomlin, a copper pipe was loose from it's proper home & therefore not supplying fluid to the servo when selecting 3rd gear & it had obviously happened before as there are signs of solder on the end where it fits into the valve body, presumably an attempt to make it a tighter push fit. Also, there is a flat worn on what is the underside of this pipe where it has obviously been rubbing on the sump, so we will be refitting this pipe & making up a pair of retaining brackets to hold it & the other pipe in their rightful places to ensure this doesn't happen again! Aside from this, there seemed very little else out of place or untoward, so hopefully this will solve the trans problem, fingers crossed.
Going back to the engine, one other issue that appeared whilst doing all this work was that when I removed the rocker cover, after a while a river of oil was spotted running down the block. Incidentally the oil was extremely thick & gooey yet clear & I put that down to the fact that when I'd changed the oil & filter earlier this year, I'd put in some oil additive, so that seems to work well!!
A quick check revealed that due to the "lean" of the engine, ie tllted over to the offside, any oil in the rocker gear was draining down to the lowest point which was over 1 & 2 plugs & around their respective valve springs, finally flowing over the edge of the cylinder head & down the block. So once the leakdown test was completed, the rocker cover had to be refitted to prevent any further mess. This leads us to wonder if some sort of drain system needs to be engineered to prevent this & also to aid oil recovery in the sump. This may also be contributing to the excess oil being blown out into the catch can, as there are two vent pipes, one from the conventional oil breather in the block & one from the rocker cover. This earlier pic shows the engine lean, dictated by the placement of the blower & its closeness to the upper chassis rail on the nearside.
So, whilst these components are out of the chassis, it gives me a chance to do some spring cleaning & also figure out a more direct & easy route for the throttle linkage. As it is, after running under the forward section of floor & through the motor plate(!), it goes through a complicated series of bellcranks & under the starter motor before connecting to a long cable that goes up & over the engine to the injector! This last bit was the start of my mission to improve the situation, as it's impossible to remove the rocker cover without first removing the throttle cable which seems to me to be a design fault that needs attending to whilst we're here (the above pic also illustrates this point as well!).
So that's it for now, the trans gasket was ordered that night & should be with Dave now, so once the trans is buttoned up again, he can get it off the stand & make some adaptors to mount the engine ready to strip that down to see what horrors we will find. Whilst we're at it, I think we'll be doing a check over everything just to be satisfied that we've utilised the opportunity to ensure it's all in tip top condition, ready for the coming season.
Oh, & I'm still looking at ways of getting a tacho fitted or maybe even a shift light, to make launches & gear changes easier to gauge. Dave has a very trick little one fitted to Scott's JD, but it could be hard to see as it's got a very small unlit digital display, but we will investigate further.
Re: Spirit ?
PostPosted:Thu Nov 19, 2015 11:26 am
Unbelievably today is the first time I've looked at this thread, so I figured that as I'm slightly involved that I should post something if for no other reason than to automatically get future posts!
I have no doubt that the gearbox issue is down to the dislodged pipe - which is an easy fix. It's been good to look inside the 'box etc. as until now they have been a bit of a mystery, and while I had a clue as to what was going on I couldn't be sure. The clutch is an interesting piece of work, and at this time doesn't allow for much in the way of adjustment as there are no weights currently on the fingers.
As for the motor, once it's on the stand I don't expect to see anything too untoward, however I have no doubt we have a head gasket issue I'm hoping that we can do something to prevent a reoccurrence.
I for one can't wait to get a little bit of 'pop' into the car!
Re: Spirit ?
PostPosted:Wed Mar 02, 2016 10:43 pm
A belated update following on from Dave's last posting.
We got the engine up on the stand & stripped the head down & took the sump off.
Upon removing the head, we discovered confirmation that our initial thoughts were correct as you can see from the pic below, a blown head gasket between cylinders 2 & 3 (the narrowest gap in the engine!).
Incidentally, this is one of the two gaskets fitted, this one is below the spacer plate & there's an identical one above it! Naturally we checked the bores & the pistons & rings & whilst nothing untoward was found, we have fitted new rings just in case. Dave took the head, pistons & rods down to a BMC guru near him for expert analysis & the concensus was that the bearings would go again but new rings would probably be wise at this stage, even though there were no obvious signs of faults with them.
We tried to remove the main bearing caps but as the front & rear carried spacers for the sump gasket which had been superglued on, we couldn't budge them with out causing further possible problems, so decided to leave well alone. The small end bearings showed no appreciable signs of wear so we hope the big ends were the same!
Whilst underneath, we took the opportunity to address the rather sorry looking oil pickup filter & fitted one of Dave's ones he manufactures for Caterham 7s. We also marvelled at the bottom end girdle we had seen before when we removed the sump in situ, the amount of work carried out to the rotating parts etc is very reassuring!
The head was cleaned & checked & found to be slightly warped so 6 thou was skimmed off & then, because we decided to fit superior Iskenderian double valve springs, discovered that they were a few thou taller than the original ones (Special Tuning, we think) so had the valve pockets re-machined to accept them. According to the BMC guru, the pistons are also +20 Special Tuning ones, although we're at a loss to understand why there are 4 holes drilled just below the bottom ring land!
Hopefully by the time you read this the engine will be all buttoned up & ready to be put back, together with the mended transmission, so I'll be headed down to RDR HQ for another work day. Also another job to be done is to modify the new trailer I just bought for the car, a fully-enclosed one that needs a smidgen taking out of the side rails for the tailgate aperture in order to get the front wheel hubs to pass through! This trailer was originally built for a Junior Dragster (the later type with leafblower motors!) on a stainless steel chassis with fibreboard panels & aluminium frames & whilst long & tall enough, needs this minor amount of work to get the car inside it.
I didn't really need a new trailer as we've modified Dave's truck to take it & his altered (& Scott's JD as well) together, but if I wanted to take the dragster somewhere on it's own without the hassle of using Dave's truck, I can now using this. Plus, if Dave needs the space, we can load the car in the trailer to give him more workshop space, or even use it himself for Scott's car or moving long thin things around!!
More news as & when the engine & trans are re-fitted & some testing is/has taken place, looking forward to the new season!!
Re: Spirit ?
PostPosted:Tue Mar 08, 2016 4:17 pm
Thanks for the update Maurice.
I look forward to seeing the car run again.
Re: Spirit ?
PostPosted:Tue Mar 29, 2016 7:28 pm
Haven't been on here for a while.
When I first had the car it had an AP twin-plate racing clutch. This was too fierce and resulted in a lot of gearbox and back axle breakages. I built a slider from Russ Carpenters plans but only had room in the can for one plate, so even with a lot of weight on the arms it worked, but slipped too much. I then fitted the clutch which is in there now but only raced it a couple of times with that clutch.
I must apologise for the clutch release mechanism, I made it up out of bits to try the clutch and never got around to changing it. Tight in there isn't it.
Glad the gearbox problem was just a lose pipe.
Dave Miller had a trick for the head gaskets. Ease up the lip and insert copper wire under it. When it is tightened down it forms a good tight seal. Never had any problems with blown gaskets.
I was probably the last person to completely strip and check the engine in about 1993, not done many miles since. (not guilty about the superglue) When I took the head off I found a large gouge in one of the piston walls just where the gudgeon pin was. The pin was press fitted and didn't appear to have moved so I got Oselli to sleeve the bore and check the piston, obviously been OK since.
Dave Miller had the con-rods and crank polished and nitrided and as you say the girdle is a work of art.
Hope to see the car out again this year.
Re: Spirit ?
PostPosted:Wed Aug 31, 2016 8:48 pm
I guess it's time for a long-overdue update on things. As some of you may know, we attended Dragstalgia this year (2016) & had a very successful weekend. With the repaired transmission & refurbished engine, the car went very well with every run improving on the previous one culminating in a best time of 12.74 & finally a best speed of 111.54 mph!
However (there's always one of them, isn't there?), despite repairing the trans it seems there's still an issue with it. Changing into 3rd gear position as I understood it to be & how everything I've seen & been told it should be, resulted in the engine screaming it's head off! This was only resolved by treating that position as being 1st gear, however that then begs the question as to what the other positions are. Once I began launching using the "new" 1st gear, it was no longer screaming through the lights & produced the time & speed above, treating the shift pattern as a straight sequential one. Further investigation is called for this winter!
The engine seems fine now, although it managed to fill the oil catch can on every run, but we think that may be due to overfilling (on the last couple of runs I didn't re-fill it) & keeping a close eye on the oil pressure & dip stick measurements seemed to show it had settled down & no more was spat out!
We did have one more issue, the starter motor failed in the pairing lanes & we had to tow back to the pits & investigate. After stripping half the accessories off the engine, we managed to remove it & stripped it down. It appeared that the terminal post was slightly loose & was turning when tightening the battery lead, resulting in it toucjing the end casing, as the small plastic insulating sleeve had broken up! A quick bodge with fibre washers & electrical insulating tape cured the situation & all was well for the remainder of the event. I now have a replacement insulator & will rebuild it during the winter.
Due to various issues & other events, I won't be running at any more events but will be displaying it at the new Gatwick Aviation Museum show on the 4th September, organised by my old friend, Mike Lintern of American Autoparts.
That's all for now, see you all next year.
Re: Spirit ?
PostPosted:Mon Sep 05, 2016 11:05 am
Used to be, middle first, full forward second, full back third. No neutral.
Re: Spirit ?
PostPosted:Thu Feb 02, 2017 3:49 pm
Again, I've just logged back in again & thought I should post an update.
Most of the work lately has been on the trailer to make it fit & usable for the car. Fitted proper tie-downs front & back using some alloy checkerplate panels kindly donated by my fellow team member Dick Hogben. This was because the floor board near the back was rotten & beginning to degrade & wouldn't have been a suitable place to mount tie-downs to. With what was left over, I made a similar plate for the front to mount the electric winch & the front tie-downs so I feel confident it won't break loose in there.
I now have a matching checker-plate box to mount on the draw bar to house the battery for the winch & the interior lights (when I get around to fitting them). Next job is to make an alloy angle framework inside the front bulkhead to have a shelf to carry stuff on over the front wheels, originally to hold the battery but the weight meant it was safer to put it outside.
Still have to do anything about the throttle cable & the starter motor problem & still mystified by the trans shift anomaly. It definitely felt better using the 3rd gear position as first gear & I wonder if the rebuild it had before it was stored & not used again, resulted in the pipes being transposed. However, the 2nd gear position, ie fully forward, definitely didn't hold it back going through the lights & did not make it scream like the 3rd gear position did. So I'm going with the sequential 1-2-3 pattern for now to see how that works out.
As Dave will not be out with the Nostalgia Funny Car this year, it looks like we will be out & about a bit more this year so come & say hi if you see us.
Re: Spirit ?
PostPosted:Sun Feb 05, 2017 7:20 pm
Thanks for the update Maurice.
How many meetings are you doing this year?
Sorry to hear that Bubblegum won't be out though although I'm looking forward to seeing Dave's altered out again.