Spitfire Engine and gearbox out. Now what?

[Banksy82]

22 minutes ago, JumpingFrog said:

Just to point out, unless I misunderstood, you're refreshing a Mk. IV 1300 Spitfire engine. You definitely need the "uprated pump" . The whole reason for its existence was to increase the flow/volume (not pressure) to supply sufficient oil for the larger journals of the later "big crank" engines.

Not for the first time I am an idiot! Yes of course this makes perfect sense. Repair kit it is then.

[standardthread]

12 hours ago, JumpingFrog said:

You definitely need the "uprated pump" . The whole reason for its existence was to increase the flow/volume (not pressure) to supply sufficient oil for the larger journals of the later "big crank" engines.

Sorry, I totally disagree on 'the need'.

If you refer to my previous post about using a DG series short block, the car it went in, my Herald estate, was a daily driver car, we also used it on very long high speed journeys for holidays in Scotland, single trip 330 miles one way in eight hours , on motorways and A roads, such as the A9 with a couple of stops for food and petrol. Total mileage for a week was 1100 miles plus.

The engine has covered just over 50k, the pressure, which would by this mileage have dropped if there was 'a need' for the later pump, is still as good as the day I first turned the engine over.

In addition to that, I fitted an oil cooler to the car on the re-build, which if there was 'a need' for a high volume pump would have caused significant oil issues?

[JumpingFrog]

We will agree to disagree, it's fine if you believe "need" is too strong of a word. But my point remains, the later pump is the correct pump for the engine. In my opinion doing anything else is entering uncharted territory, Triumph thought it was necessary to increase the size of the pump.

Whether or not this was one of the misguided things they did, I don't know, like the recessed fire rings on late blocks that cause more problems than flat blocks ever did.

I don't have experience of downgrading the pump, but it's reassuring to hear that there is enough excess capacity for this case.

FWIW, I'm now curious what pump the late GK-prefix Herald 13/60 got which will be almost the same as your DG block.

Edited October 16, 2022 by JumpingFrog

[glang]

Out of interest does anyone know where the six cylinder alloy pump came from? Was it used in the last cars with that engine?

[Clive]

11 hours ago, glang said:

Out of interest does anyone know where the six cylinder alloy pump came from? Was it used in the last cars with that engine?

Certainly an alloy pump on the 2500s engine I used in my vitesse. I am guessing it changed at the same time as the 4 cylinder, but no justification apart from it would make sense. (I know, we are talking BL here)

[RobPearce]

I thought all the sixes had alloy pumps.

[glang]

No, my Mk1 Vitesse had a smaller cast iron one with no intake strainer until recently. Now fitted what is sold as 'up rated' bigger alloy unit. Now read a post where the old type were preferred because being all one metal the internal clearances dont change so much with temperature changes....

[RobPearce]

Is yours an early, small journal engine? I was fairly sure that both my Mk1 Vitesses had alloy ones even though neither had the strainer.

[standardthread]

17 hours ago, JumpingFrog said:

We will agree to disagree, it's fine if you believe "need" is too strong of a word.

I don't have experience of downgrading the pump, but it's reassuring to hear that there is enough excess capacity for this case.

FWIW, I'm now curious what pump the late GK-prefix Herald 13/60 got which will be almost the same as your DG block.

Agreed!

The capacity is obviously there. The pump I used must have come from an engine that predates my 'J' reg estate, but that has (had) a GE series engine in.

As for the short DG block (DG4949ESS) I used, I don't know its age, I picked it up from a Triumph dealer having a clearance sale in about 1981 for £40, happy days.

Triumph (BL) were good at doing things not 'in the book', my 1300 Dolomite has parts on it shouldn't have, potentially larger clutch, different wheel rims etc., but that could be down to clearing stock, it was the last but one built.

[glang]

4 hours ago, RobPearce said:

Is yours an early, small journal engine? I was fairly sure that both my Mk1 Vitesses had alloy ones even though neither had the strainer.

No definitely large journals. Workshop manual shows iron pump and no mention of alloy version even for mk2 engine. Dont think it was fitted as standard to any Vitesse or GT6 engine but came from somewhere else (maybe not even Triumph?) as an upgrade....

[Banksy82]

Good News!

While waiting for some parts I decided to clean out the filter on the Overdrive and lo and behold it is full of clutch material!

Sure enough the outer friction material is looking decidedly worse for wear and is loose on a couple of the rivets.

I have contacted a couple of clutch re-liners who are going to give me a quote for relining but neither seemed particularly knowledgeable. 

Are there any known companies that can reline these or are we looking at a triumph / laycock specialist (Canley reckon they can have one done in around 5 days which seems pretty good and Overdrive repair services can do one for ~ £132)

Thanks

Karl

[Clive]

Go to a specialist. You want one that is done correctly. OD spares in rugby are the other place to try. There is no real cheap alternative.

[Banksy82]

25 minutes ago, Clive said:

Go to a specialist. You want one that is done correctly. OD spares in rugby are the other place to try. There is no real cheap alternative.

Thanks, I'll give them a ring!

[Banksy82]

Hi all.

All back together and started first turn of the key. I just wanted to thank everyone for all of their input / help and to add some findings to help any future readers.

• Engine tapping audible at revs - This is now gone, could have been any number of things but my camshaft had some pitting on the lobes and most of the followers. I have replaced this with a better condition used herald unit and matched followers. (This had a slightly lower lift than the spitfire camshaft so I now have a quieter but slightly more sluggish car!) I didn't replace any of the timing chain components, big end or main bearings so these were not the source in my case. (although there were some sooty stains on the exhaust gasket that could well have been 'tapping' away due to exhaust leak??)
• Missing pin from throwout bearing carrier - pin replaced with bolt and new, (very old stock) bearing fitted along with new clutch. 
• Whine when stationary, clutch out and in neutral. - Gearbox mainshaft tip ruined - I turned down the tip and fitted a metric needle bearing sleeve and metric bearing (slightly smaller on the OD than the original imperial so a looser fit in the input shaft.) Whining noise now gone although there was a small high pitched rattle initially (could easily have been the old stock throwout bearing). No noise at all now although tunnel and carpet are back in so probably wouldn't hear anything this soon anyway. I don't think I would recommend this as a solution for others but it seems to have done the job for now. Next time the gearbox is out I will inspect and report back!
• Oil pump - replacement 'county' rotor was only just in tolerance but a combination of my outer rotor and new inner rotor closed this gap nicely. (I wouldn't reccomend mixing components but as I am planning on having the engine out again in the not too distant future I thought I would risk it. Oil pressure now 50 - 75psi when driving. 30ish at idle when warm.
• Overdrive cone clutch - Overdrive spares in Rugby relined this for me in around a 1 week turnaround door to door and were very helpful indeed regarding the OD rebuild in general.

Car now drives really rather well but I now have what I believe to be big trouble with rear bearings / driveshafts... I'll do some investigating and start a new thread if necessary.

Thanks Again

Karl

 

[glang]

Good news! With the gearbox how did you fit the new sleeve to the mainshaft tip ie. press fit, loose fit/bonded or heat and shrink?

[Banksy82]

3 minutes ago, glang said:

Good news! With the gearbox how did you fit the new sleeve to the mainshaft tip ie. press fit, loose fit/bonded or heat and shrink?

I used Loctite 603 (because that is what I had!) I went for the smallest gap recommended by the datasheet - approx .001" undersize as I recall.

[glang]

Be interesting to see how it fares but with the mileages most of our cars do these days I dont think therell be a problem....

[standardthread]

Dedication and perseverance, good on you.

[glang]

How has the repaired mainshaft tip faired Banksy? Im in pretty much exactly the same situation with an OD box Ive just bought...

[Banksy82]

I have been very pleased with the results; no untoward noises and box works just fine. 1st is sometimes a little reluctant to engage but I don't think is related to the main shaft/input shaft joint.

However...

1. I have only driven 1100 miles since the repair which I would suggest is not enough to call it a fix.
2. I haven't had the box apart since to inspect the repair so who knows what it currently looks like!
3. It required turning the tip down to 12mm from 1/2" (12.7mm) so around a 6% reduction in an already known weak spot.

With the above in mind I can't recommend the repair. I had a good number of things to do to get the car driving where I want it(still do!) so was going for the cheapest viable solution to the issues I encountered. If it was just the gearbox that needed work I think I would stump up the cash for a replacement shaft.

That being said if you decide to attempt the same I used IR12x5x16 for the race and K15x19x17 for the needle bearing. Even the branded items are reasonably priced.

As the new bearing is slightly longer than the original I also made sure the projection of the shaft through the bearing remained as it was with the original (I measured mine to be 3.0+/-0.1mm) so that the extra length couldn't cause any interference in the input shaft bore.

Also the tip is hard. Unbranded Chinese carbide wouldn't touch it. I had to use some Sandvik inserts that I happened to have knocking around. Grinding would be better if you can be sure not to temper the steel.

Hope this is of some use.

Karl.

[glang]

Thanks for the update. Ive just bought a 16mm long race and 13mm bearing as looking at the drawing I thought the 17mm might get trapped between the two shafts...

[Banksy82]

11 hours ago, Banksy82 said:

As the new bearing is slightly longer than the original I also made sure the projection of the shaft through the bearing remained as it was with the original (I measured mine to be 3.0+/-0.1mm) so that the extra length couldn't cause any interference in the input shaft bore.

This was the worry I was avoiding with the above. (I could have been clearer!)

When reducing the diameter or the tip I also turned the shoulder back so the 'extra' bearing length hung out of the back of the input shaft. 

Dimensions are such that the amount of 'tip' that extends past the end of the bearing (and therefore the clearance inside the input shaft bore) remained the same as the original.

I also bought the 13mm needle bearing but felt that it was too short.

 

[glang]

Great thanks that helps a lot and yes the 13mm bearing does look very short. Real pity there isnt a 15mm version available...