Author Topic: 998 Auto Rebuild  (Read 2634 times)

Offline MiniDave

998 Auto Rebuild
« on: May 05, 2020, 12:21:48 PM »
This motor arrived from Boston today, we've been talking about what we're going to do - the brief is to get more HP and keep it smooth and drivable. I'm not going to rebuild the auto transmission at this time, he says it was working perfectly but I will reseal it and try to keep the oil drips to a minimum!  ;D

It arrived in a shipping container I think meant for a V-8, it was laying over on its side and oil was everywhere as you can't really drain the torque converter with the sump, a couple of quarts always stay in there - most of them seem to have found their way out!

I'll tear into it in a week or so and get parts on order and send the block and head off for machine work.

More as it happens.....

When I'm done with this one he wants to send his other one out for some work - it has a 1275 (Japanese spec) and this time he's just going to send the whole car to me. See why I desperately need a bigger shop?  ::) ;D
« Last Edit: May 18, 2020, 08:30:20 PM by MiniDave »
1989 Cooper Racing Green
2009 Clubman S
2004 Audi Allroad 2.7 TT

Offline jedduh01

Re: 998 Auto Rebuild
« Reply #1 on: May 05, 2020, 02:23:08 PM »
Great task.,  good project but GROSS!   ! from how dirty it is / to a Auto 998...


Offline MiniDave

Re: 998 Auto Rebuild
« Reply #2 on: May 05, 2020, 02:32:03 PM »
Yep, it was pretty messy, but it'll be all shiny and pretty when I'm done with it. It's an A+, BTW.

Looking for any/all performance ideas for this motor, the only thing he wants is a smooth idle and plenty of low end torque.....other than that I can do anything I want within reason. He already got me a  new HS4 so I'm planning on the "stage One " kit with the RC40 exhaust, header, intake and so on.

Looking at 40 over flat top pistons, bigger valves, can't decide whether to go with the Evo1 MiniSpares cam and run regular 1:13 rockers, or go with the Evo2 and 1.5 rockers....of course they're out of the 1.5's right now......the Evo1 can give a lumpy slightly erratic idle in a small engine....I don't think he'd go for that.
1989 Cooper Racing Green
2009 Clubman S
2004 Audi Allroad 2.7 TT

Offline jedduh01

Re: 998 Auto Rebuild
« Reply #3 on: May 06, 2020, 12:52:05 PM »
I personally wouldn't hesitate the .040 - .060 Flat tops + Evo001 Cam. 

After CMU last year, I knew i needed to replace the 2nd gear synchro in my Moke... Engine was coming out + it burned some oil by not being bored previously so its time to tend to the motor too.

I did exactly that. . 040 Flat tops + Evo001 Cam...

going from stock (dished pistons ) and 998 head. (lower comp for sure ) to the Same head and bigger bottom end the end result was NOT Earth Shattering in power making.

   The cam DOES pull better feel better in the upper RPM Ranges.  Perhaps the extra CC"s and compression help a "lump' in the small bore.. but I dont notice it (maybe a tiny tiny bit at cold idle)

My pickup has .060 Flat top 998 -  with a 1275 Head... ,Maifold + single HS4.   Side by side they run Nearly the same.. and with this combo... i would wager these peppy 998's run as good as a poor running 1275.


Moke setup:
Standard 998 head
.040 Flat top pistons
Standard Sintered rockers
HS4 Single carb
Cast manifold
3.44 CWP

Pickup setup:
  .060 Flat tops
 1275 13g16?? Head
Standard sintered rockers
Single HS4
Cooper freeflow manifold
Magic wand gearbox
 3.2 CWP

If its opened up = i agree go for it = only SOOO much you really can do to a 998.... without going nuts nuts...
 
I know ill build another like it for whenever needed, 2 cores in storage.

Offline MiniDave

Re: 998 Auto Rebuild
« Reply #4 on: May 06, 2020, 01:07:06 PM »
So going to the 1275 head didn't make that much difference over the 998 head? Good to know....

I'm not expecting huge gains, but I was hoping for a little more snap at the bottom end and a little freer running as it revved. I also will put the "Stage one" exhaust and manifold on and ditch the cast iron one...that's supposed to help as much as 20% improvement in both HP and torques?

I'll tear it down next week and see where I'm at.....I was thinking to go ahead and get the 60 over pistons - go for all of it while I'm in there as I know he'll never rebuild it again. It's a car for his wife to drive in town - and they live in Boston, so high speed is not part of the equation.
« Last Edit: May 06, 2020, 01:09:53 PM by MiniDave »
1989 Cooper Racing Green
2009 Clubman S
2004 Audi Allroad 2.7 TT

Offline MiniDave

Re: 998 Auto Rebuild
« Reply #5 on: May 07, 2020, 05:04:13 PM »
Did the A+ 998 come with flat top pistons? Cause this one has them....

Popped the head off just to see what it looked like.

Plans right now are new, larger valves, a little head work, flat top high compression pistons, Evo1 cam, new springs, new valves, new lifters, bearings, 60 over pistons etc.
« Last Edit: May 07, 2020, 05:34:53 PM by MiniDave »
1989 Cooper Racing Green
2009 Clubman S
2004 Audi Allroad 2.7 TT

Offline MiniDave

Re: 998 Auto Rebuild
« Reply #6 on: May 09, 2020, 08:01:37 PM »
After looking up the specs via the engine tag, it turns out these A+ 998's did have flat top pistons after all. As part of the rebuild we're considering changing the final drive ratio to a 3.44 as this has a 3:1 for fuel economy, some of them came with a 2.95! This car is strictly an in town car, so he's not concerned with highway RPMs and I think that would help with the stop light grand prix as right now he says it's pretty slow getting away from a light!

I micc'd everything up and am putting together an order to go in to MiniSpares tomorrow, I'll be interested to see both the cost and the time it takes to get parts from them as they claim they're running short staffed and reduced hours right now. I just have a feeling this Brexit thing is going to bite us in the ass on parts at some point, either via reduced availability or increased cost - or both!

I had a heck of a time finding a rear crankshaft seal for this, as the automatic seal is different than the others - I finally found one in Connecticut of all places - at an online store called Sports and Classics......correct part number and description and way cheaper than either Mania or 7Ent - and neither of those places had it in stock anyway. Minispares didn't even list it  - Somerford had a part number listed, but no stock and so on. Spares does sell a gasket kit, but as usual no seals are included. There are a couple of specialty o-rings that I can get from Somerford but on one else seems to stock them and NO ONE carries an oil pump for an automatic - luckily I think this one is fine, there's no scoring inside so I'm planning to just use it.

Pulling the flywheel was interesting too - there are six bolts around the main crankshaft bolt - you remove three of these to install the puller much like on a manual flywheel, but if you take the other three out the torque converter is now junk. The first time I tried to remove it, it pulled the washers up around the heads of the bolts on the puller so I had to go find some heavy duty washers. It's always exciting when one of these comes off cause they usually release with a bang - and this one was no exception!

Once the parts get here I'll send the head and block off to be machined - that could take a while too as the last time I checked the machine shop was backed up 6 weeks....we'll see if they've caught up any.

I'm also going to call for some new parts washer fluid on Monday as this stuff's pretty dirty and I have a lot to clean up.

I found a freeze plug under the torque converter that was clearly leaking oil too - I'm thinking I'll probably just pop it out and clean it then re-install with JB weld for sealer......one of the local brit car shops says they always use it on their cars with no adverse effects.

The bottom pic is what a Mini automatic looks like inside....
« Last Edit: May 09, 2020, 08:07:25 PM by MiniDave »
1989 Cooper Racing Green
2009 Clubman S
2004 Audi Allroad 2.7 TT

Offline tsumini

Re: 998 Auto Rebuild
« Reply #7 on: May 09, 2020, 10:06:07 PM »
Is that a crack between #2 and #3 cylinders?

Offline ADRay

Re: 998 Auto Rebuild
« Reply #8 on: May 10, 2020, 07:55:34 AM »
looks pretty darn clean compared to mine  ;D
1982 Mini 1000 HL

Offline MiniDave

Re: 998 Auto Rebuild
« Reply #9 on: May 10, 2020, 09:02:20 AM »
No crack - it would be pretty difficult to get a crack there due to the amount of metal - not saying it's not possible, but I can't think of how that would happen short of a catastrophic failure of some sort.

This engine ran fine, it just was worn down I think....it is very clean inside. No idea how many miles on it but it's clear the owner changed the oil plenty frequently. Once I pull the transmission apart to change the diff we'll see if there's any sludge in the bottom, but I doubt there will be.

This will be strictly a run around the city car - and since the traffic in Boston is brutal, I doubt it will get a ton of miles on it. He just wants to be able to zip around in it, home and back, out for coffee - that sort of thing.
1989 Cooper Racing Green
2009 Clubman S
2004 Audi Allroad 2.7 TT

Offline jeff10049

Re: 998 Auto Rebuild
« Reply #10 on: May 10, 2020, 03:00:12 PM »
Fun project I thought that looked like a crack too glad it's not.

Changing the final drive will probably make all the difference in an auto car.

 Do they have high stall converters for these LOL. Maybe a trans brake and air shifter to go with it that'll fix getting away from the stop light.


Offline MiniDave

Re: 998 Auto Rebuild
« Reply #11 on: May 10, 2020, 04:59:54 PM »
Ha! nah, this is mostly the wife's run about, he just wants to quicken it up a bit since it's unlikely to see the highway other than a quick spurt from one exit to the next around the downtown loop. I would think the combination of 38hp and a tall diff like a 3.1 would make for a pretty dull get away....if I can get it up to 50 hp and with a 3.44 I'm thinking it should be a pretty good difference.....so he'll feel he got his money's worth.

He's already said finish it up so he can send the other one out to me!  77.gif
1989 Cooper Racing Green
2009 Clubman S
2004 Audi Allroad 2.7 TT

Offline jedduh01

Re: 998 Auto Rebuild
« Reply #12 on: May 11, 2020, 10:39:27 AM »
Interested to see the steps and progress to changing the CWP.
  Just the thought of disassembling the Auto sounds intimidating.

I do have a 3.2 in my truck... was a comprimise for a 3.1 vs a 3.4 ... I like it too . Just to throw another thought.

 Are Auto CWP's same ?  No difference. Do you have the 3.44? = I have 2 sets  = need a new home.   Dont buy one.Pay shipping ill send it to you.
 

Offline MiniDave

Re: 998 Auto Rebuild
« Reply #13 on: May 11, 2020, 11:44:32 AM »
Thanks, but I have a couple of 3:44's too, I've changed several out for taller sets and the guys always say "keep it, I have no use for it now".

The last one I did recently, the guy is really excited about the transformation in his car, it's an early Mk1 with a nicely built 1275 so it pulls the 2:76 I put in it just fine. I put a 3.1 in the Inno and my friend John has the same in his, I think it's a good compromise.

As far as I know the diffs are the same, they would have wanted to use as many corporate parts as possible so I'm pretty sure it's the same design, the ratios that were used are the same as the manual gearboxes too.

I haven't pulled an auto apart in decades, so this will practically be all new for me too. Hope I remember how. Last time I did it was to change out a case that had been worn thru on both sides of the final drive by bad rubber u-joints.
1989 Cooper Racing Green
2009 Clubman S
2004 Audi Allroad 2.7 TT

Offline jedduh01

Re: 998 Auto Rebuild
« Reply #14 on: May 11, 2020, 02:32:37 PM »
Regarding Mini Spares:

Instagram posts shows a great shot of all the Shipments to go out the door. Props to the teams for packaging overtime +  Output.  I only wonder about stocks - China / Suppliers output had to have been delayed in some components ... All the UK Stay at home orders just like us have us all shopping and ordering..
  Good to see! 

https://www.instagram.com/p/CADqmrRDagh/?igshid=1lhl22telmduc


Offline MiniDave

Re: 998 Auto Rebuild
« Reply #15 on: May 11, 2020, 02:56:45 PM »
A ton of stuff was listed as out of stock, I'm scrambling trying to find some of the stuff I need.

No shortage of business on their end, is there?

I also wonder about DHL, whether they're running short staffed too?
« Last Edit: May 11, 2020, 02:58:26 PM by MiniDave »
1989 Cooper Racing Green
2009 Clubman S
2004 Audi Allroad 2.7 TT

Offline CooperTune

Re: 998 Auto Rebuild
« Reply #16 on: May 15, 2020, 08:19:36 AM »
I love to be wrong, but I have  always thought the auto CWPs are different.

The late and auto A+ 998 engines I have stripped have the 10 to 1 flat top press fit pistons. I like the rods
so I have a large collection of floated 998/1100 con rods.

My 998s are bored .060 O/S balanced with two part S balancer and ultra lite flywheel and back plate. 
Deck block for .005 piston to deck. I use 295 castings with the slightest touch up in ports and bowls.
Hard exhaust seats, O/S intake and exhaust late triple groove valves. Springs to match cam and surface
to reach 10.2 to 1 C/R. The Cooper one pc. header is perfect for just about anything you want to do. My
next one gets twin 1 1/4 s most get a single HIF38. I tend to use 1.3 Cooper S rockers. I have built this
package with SW5, MD266, and MG Metro cam I have not driven any of these but each was as per
customer request and no complaints yet. Steve (CTR)

Offline MiniDave

Re: 998 Auto Rebuild
« Reply #17 on: May 15, 2020, 10:24:45 AM »
That sounds almost exactly what I'm doing, Steve. I think it should make a good package. I haven't torn this transmission down yet, so I don't know for sure, but from what I can see of it the CWP looks the same....and the ratios offered are the same as for the manual transmissions so it makes sense to me they would use the same parts where they can.

Since AP only makes the trans and not the diff, I'm hopeful I can swap it out.

I'm going to dig out my copy of Vizard's book and see if he talks about the 998 heads, if so I'll follow his recommendations...unshroud the intakes at least. I have a "Stage One" kit coming for it too. I wanted to use the Cooper S rockers but everyone is out of stock on them, Maybe I can get some before I'm ready to finish it up.

Any thoughts on using the 1.5 rockers instead ? (Of course, they're out of those too)
« Last Edit: May 15, 2020, 10:31:04 AM by MiniDave »
1989 Cooper Racing Green
2009 Clubman S
2004 Audi Allroad 2.7 TT

Offline CooperTune

Re: 998 Auto Rebuild
« Reply #18 on: May 17, 2020, 08:47:16 AM »
I have always found using 1.5 rockers tends to take away from low end and only add to the top end. I have a NOS set of the KD 1.5
rockers ( yes the pretty ones ) I have yet to find a project for.  Recently I have been thinking lately about returning to Solo 2. While running Solo 2 in the 70s I ran a 1275 Cooper S bored to .060, 13.3 to 1 CR, ST 643 cam, 45 DCOE Weber, SC /CR, 4.35 CWP.  I'm
leaning toward building a 1071 for a new autocross car. I'd love to find a set of S size six inch con rods with a std pin bore. It would
save chopping a big slab off a block. Steve (CTR)

Offline MiniDave

Re: 998 Auto Rebuild
« Reply #19 on: May 17, 2020, 08:57:47 AM »
My MiniSpares order was charged to my card last Tues but I still haven't received a shipping notice from DHL - or any parts for that matter. One week so far since I put the order in.

Of course I found that I had forgotten a few things, fortunately Victoria British is now open again and they show the items in stock and for close to the same price once you factor the exchange rate and shipping.

Wow Steve - 13.3:1 compression ratio? That's significant! With a 4:35 CWP, 1st gear was only to get moving, right? After that you ran the course in 2nd and maybe touched 3rd once in a while on a long course?

I had a 1071 Cooper S way back in the day, it was a sweet little motor!

I found the std ratio forged rockers locally, so I'll go with those instead of the 1.5's.
« Last Edit: May 17, 2020, 09:02:03 AM by MiniDave »
1989 Cooper Racing Green
2009 Clubman S
2004 Audi Allroad 2.7 TT

Offline MiniDave

Re: 998 Auto Rebuild
« Reply #20 on: May 17, 2020, 09:56:13 PM »
Well Steve, your memory is way better than mine, it does look like the CWP is not interchangeable, just a cursory look tells me the crown wheel is way bigger on this than on a manual. I had to pull the covers off anyway as there was oil and grunge all over this thing and I was always planning to reseal it, new gaskets, axle seals, end cover seals and gaskets and so on, but I don't plan to go any further in the disassembly.

Like I said, it's been decades since I had one of these apart.....maybe 5 of them!

Tomorrow I'll dig out a 3:44 and post a pic to compare the size. It also looks like it takes a very special socket to get the gear off so the pinion could come out and I'd have to have one of those made as I seriously doubt anyone in the US has one to loan.

I got the block and head cleaned up ready to go to the machine shop - I could have taken it all muck covered as they're going to boil it out anyway, but I know I wouldn't want to get one in like that, so fair play to all.

I've got a lot of the side covers cleaned up for the transmichigan, but now I'll have to get the main body in the tank so I can clean it up too and I need to do that in a way that won't get grit in any of the components that are still in there. Should be interesting. I don't want to take the whole thing apart but if I can't get it clean enough and not get crap inside I may be forced to.
« Last Edit: May 18, 2020, 08:27:49 PM by MiniDave »
1989 Cooper Racing Green
2009 Clubman S
2004 Audi Allroad 2.7 TT

Offline MiniDave

Re: 998 Auto Rebuild
« Reply #21 on: May 18, 2020, 08:26:44 PM »
As Steve pointed out, the diffs are different between manual and auto transmissions, the pic gives a pretty graphic example of HOW different!

When I went to Someford's site they list them and show the ratio for this gearset as 3.27 so not a huge difference to the 3.44 I had hoped to use.

So I'll carry on as we had planned....

Found DHL has my parts and expects to deliver them by Wed end of the day - I found out because they sent me tracking info which showed them going from England to Hong Kong, then to Germany.....seems like a really long way to go around the block to get to Germany (where the DHL hub is) and then to the US.

Went over to Harbor Freight to pick up some more inexpensive wire brushes - they work really well to get the grease and much out of the pores of the aluminum as he wants the transmission case painted too, so I need to get it really clean so the paint will stick.

Went up to Vicky Brits to get some forged rockers - they had 7 and no idea when they would have more. That's the way my whole day went today!
« Last Edit: May 18, 2020, 08:31:49 PM by MiniDave »
1989 Cooper Racing Green
2009 Clubman S
2004 Audi Allroad 2.7 TT

Offline MiniDave

Re: 998 Auto Rebuild
« Reply #22 on: May 20, 2020, 11:18:33 PM »
Forging ahead......a load of parts came in today for the 998 build, tomorrow I'll run the block and head up to the machine shop so they can start on the machine work.
1989 Cooper Racing Green
2009 Clubman S
2004 Audi Allroad 2.7 TT

Offline 94touring

Re: 998 Auto Rebuild
« Reply #23 on: May 20, 2020, 11:27:41 PM »
Going with twins or a single carb?

Offline MiniDave

Re: 998 Auto Rebuild
« Reply #24 on: May 21, 2020, 12:17:13 AM »
Single HS4, that's an extra manifold - originally got it for Clancy but he couldn't make twin carbs work on the Moke, so we went with a single carb manifold and an HIF 38 on the Moke.
1989 Cooper Racing Green
2009 Clubman S
2004 Audi Allroad 2.7 TT