240 General: New (to me) 1980 Volvo 244

[Othen]

Originally Posted by Clifford Pope

Well, it seems our experiences differ then.
In my experience with 240s what gradually happens is the valves become noisier as the gaps slowly widen - I've assumed because the shims wear from contact with cam lobes. There isn't usually a visible groove because the buckets should rotate freely, so the wear is spread over a dish shape, not concentrated in a groove because the bucket isn't turning. Also the cam lobes wear, increasing the clearances.

I've never actually had a 240 with any significant valve seat recession. The heads are I think all built to run on unleaded fuel, unlike most other older cars.

So I come back to my point - you need to know the thickness of the current shim before you can fit a new one, in order to have a base point. Or of course you put in temporary shim of any known thickness, eg a new marked one, measure the gap, and then calculate the size you need from that.

If only the shims ever wore, then you could just put in new ones of that size to get the valve clearances correct. Or if shims never wear, then you just need to get new ones to take up any wear in the other components.
But if wear takes place in an unknown mix of shim, valve, valve seat and cam lobe then you don't have a known starting point.

Finally of course, the engines go for hundreds of thousands of miles without any significant change in valve clearances, so you probably only need to reset everything once in your lifetime anyway.

Good morn Clifford,

Thank you so much for that - your answer is a really good example of why this forum is so valuable.

The RB has been the first Volvo I have ever worked on in a meaningful way (the new 240 I bought in the mid-1980s was under warranty always maintained by the dealer in Germany). I have no other experience with B21 engines (and most my mechanical experience has been with bikes rather than cars).

I had no idea that valve shim wear was a common problem with B21 engines, so I thank you for that. I'm still a bit surprised to hear that is a common fault, but only because with bike engines wear at the cam and followers is almost unknown, but valve seat wear (only really at the exhaust valve, I've never come across a problem with the inlet valves) is quite common. Perhaps the reason is that bike valves are much smaller (nearly all 4 valve heads), run much faster (12,000 RPM is not uncommon, some as high as 15,000 RPM) and they probably run hotter (more air cooled motors, and the water cooled ones don't have room for such big radiators).

So, I bow to your superior knowledge of B21 engines, it does though make my spreadsheet record and plan to use it to predict what size shims I might need in advance completely redundant if it is the shims themselves rather than the valve seats that wear out on Volvos.

I agree with you about engines rarely needing valve adjustment. I have checked the clearances on two of my bikes (a Triumph parallel twin and a Suzuki V twin) in the past year or so. Neither needed any adjustment, which was particularly surprising for the Suzuki (a DOHC design with 4 camshafts and 8 valves) in that it had covered 135,000 miles and is red-lined at 11,000 RPM:



I thought I was being really clever in keeping a record of the shims I'd fitted for each valve, so I'm sorry to hear that for a Volvo it has been a waste of time, but thank you for your knowledge on this matter.

Alan

[Clifford Pope]

Sorry, I didn't mean to suggest that valve shim wear was a common problem, simply that IF wear does occur, then in my experience the valves get noisier because something has been wearing, quite probably the shims.
But it's not in general common in our Volvos I don't think.
Also if the gaps do open a bit, for whatever reason, it doesn't really matter too much - better a slight rattle than the gap closing and the valve burning out.

Of course it depends a lot on how the car has been maintained. If oil changes have been neglected and the engine has spent long intervals sitting unused in filthy oil then it will wear out much more quickly.

[Laird Scooby]

A few points to further consider - wear at the cam lobe won't alter the measured clearance as that is measured between the top of the bucket and the base circle of the cam.

Second, shims don't wear, they are case-hardened to prevent this unless some monkey has been at them with a lapping table!. There is no right or wrong way up to insert them (no markings of "UP") so they must therefore be case hardened on BOTH sides.

On other engines with a rocker and pedstal acted on by the camshaft to open the valve such as the Ford Pinto, Mercedes OHC and Nissan/Datsun OHC from the 70s/80s as three examples, they have wearing points, notably (but not limited to) the rocker pad, the rocker tip and the rocker ball socket that sits on the pedestal.

For this reason, valve clearance will almost always increase on these engines - like wise on pushrod/OHV engines as they have a similar rocker arrangement albeit with a pushrod and a tappet/follower sitting on top of the camshaft to transfer the motion. Note that on some OHV engines, it's quite common for the bottom of the tappet/follower to become dished by the camshaft resulting in excess clearance between rocker tip and valve stem.

Back to the redblock OHC motor, the cam operates directly on bucket tappets with shim clearance adjustment. This means much fewer wearing components so the clearances stay as they should a lot longer.
Regardless of all else, the main wearing point is going to be the top of the valve stem and/or the underside the the bucket. The shim should not wear at all.

On the Vauxhall Slant-Four engine, a similar arrangement is used but the shim is replaced with a hex-drive grub screw (use an Allen Key) with a tapered flat on one side of it. Winding the screw in or out altered the clearance.

However, in common with the redblock OHC, the need to adjust the valve clearances was vastly reduced over the other engines cited earlier because of much fewer wearing parts. Regardless of this, the clearance always increased - VSR was never a problem with either of those engines, largely because they were designed for unleaded fuel.

However because the rate of wear on the wearing parts is much lower, it took longer for any abnormal clearances to be noticed/heard.

Unless any of your shims have been ground down Alan, you should be able to apply your theory of using your spreadsheet with excellent results.

[Clifford Pope]

Wear at the cam lobe won't affect the clearance, but the cam lobe rubs on the shim, so the shim is bound to wear too, perhaps only a little as the bucket is meant to rotate to spread the wear.

I assumed both sides of the shims were case-hardened, but obviously a ground side would be placed on the bucket side, where absence of case hardening wouldn't matter.

[Othen]

Originally Posted by Laird Scooby

A few points to further consider - wear at the cam lobe won't alter the measured clearance as that is measured between the top of the bucket and the base circle of the cam.

Second, shims don't wear, they are case-hardened to prevent this unless some monkey has been at them with a lapping table!. There is no right or wrong way up to insert them (no markings of "UP") so they must therefore be case hardened on BOTH sides.

Unless any of your shims have been ground down Alan, you should be able to apply your theory of using your spreadsheet with excellent results.

Many thanks Dave,

I'm more than a little confused now. I'm sure I'll work it out.

Alan

[Laird Scooby]

Originally Posted by Othen

Many thanks Dave,

I'm more than a little confused now. I'm sure I'll work it out.

Alan

The fixed shims take the place of the mechanical adjuster Alan, other than that it's no real difference to normal valve adjustment. Just don't grind the shims down, do it as you have and you'll be fine. You can still use your records of shim size. No problems!

[Othen]

Originally Posted by Laird Scooby

The fixed shims take the place of the mechanical adjuster Alan, other than that it's no real difference to normal valve adjustment. Just don't grind the shims down, do it as you have and you'll be fine. You can still use your records of shim size. No problems!

Many thanks Dave.

Alan

[Othen]

The RB continues to return almost exactly 25 MPG: 218 miles on a shade under 9 gallons (40l). I'm quite happy with that (well, I'd be happier it it did 50 MPG!) - I think 25 MPG is much what it would have returned as a new car (on short journeys and mostly in town).

I've started using Reddex fuel system cleaner - mainly because Tesco is selling it at half price, so a £2 bottle is good for about 500 miles (2 tanks). I think it does improve the RB's general running.

[john.wigley]

Originally Posted by Othen

The RB continues to return almost exactly 25 MPG: 218 miles on a shade under 9 gallons (40l). I'm quite happy with that (well, I'd be happier it it did 50 MPG!) - I think 25 MPG is much what it would have returned as a new car (on short journeys and mostly in town).

I've started using Reddex fuel system cleaner - mainly because Tesco is selling it at half price, so a £2 bottle is good for about 500 miles (2 tanks). I think it does improve the RB's general running.

Good call, Alan. I first used Redex in a '51 8HP SV Ford (my first car) in the mid sixties. At the time, it cost one (old) penny a 'shot', when 'regular' fuel was 4s11d per gallon. Four gallons plus four 'shots' cost exactly £1, which, as an apprentice on less than a fiver, represented my motoring for the week! That, and half a gallon of 2T in my NSU Quickly for riding to and from work and 'tech when it was fine - happy days!

Regards, John.

[Othen]

Good morn chaps,

I was watching a TV programme called 'Vintage Voltage' the other eve (one of those slightly irritating scripted reality programmes with a very irritating narrator). It struck me that the RB would make a good candidate for conversion to an EV - in about 10 year's time when maintaining an older petrol car might be problematic.

I started doing some research and found this motor for sale on eBay:

https://www.ebay.co.uk/itm/60kW-EV-M...4383.l4275.c10

Meiden 60kW EV Motor synchronous permanent magnet brushless motor (Meiden EV Motor 60kW | 9300rpm) + Resolver + Plug & tails

MEIDEN EV MOTOR 60KW SPECIFICATION
AC Motor
Part Number Y61
Input voltage 400V
Type 3 Phase synchronous perm magnet brushless
RPM 9300rpm max
Diameter 255mm (approx)
Depth 260mm (approx)
Height 280mm (approx)
Spine Diameter 20.02mm
Cooling Hose Connector Diameter 17.06mm
Mass 42Kg

... for only £585 (it is refurbished, and that is just for the motor).

I've just been outside with a tape measure and looks to me like the motor would fit into the space where the BW55 transmission sits at the moment (and the weight would be much the same). There would be no need for a clutch or gearbox of course, so I had an idea that the electric motor could have a direct drive to the prop shaft.

This motor (and bear in mind it is the first one I found - there may be more suitable units around) is 60kW and operated up to 9,300 RPM - whereas the B21A was about 70kW (when it was new) and is red-lined at 6,500 RPM, so the gearing might not be all that far out (the RB is pretty low geared anyway).

The motor needs to be water cooled - but Volvo has thoughtfully provided a radiator, although it would probably be much too big - the thermal losses should be much less with an electric engine. In that case an oil cooler type radiator mounted in about the same place would probably suffice.

So far so good: an engine that fits more or less where the gearbox goes and weighs about the same, that produces about the same power (ballpark figure) and spins at about the same speed (even more ballpark figure) and no need for a clutch or gearbox. That would make the performance about the same as it is now (which I think would be a good thing) Weight distribution would be about the same as now, but without that B21a motor and the gas tank. The engine compartment is pretty big on the RB, and probably room enough to fit quite an array of batteries and the electrical management system. The space where the gas tank was would also be available - and a few more batteries there would help even up the weight distribution.

That brings me on to batteries: which would be the problem with a project like this at the moment - in that they would cost much more than the RB is worth. I've done some ballpark calculations: the BofH talls me the B21a motor weighs about 340 lbs, which is about the same as three of these:

https://www.evwest.com/catalog/produ...roducts_id=486 (I know these are from the USA and shipping costs would be prohibitive - this is just an estimate).

... which would give 40 kWh - the same as the current Nissan Leaf, which has a range of something between 160 and 230 miles. Okay, the RB is much heavier, so let's say 4 battery racks and about 53 kWh to get 150 mile(ish) range - the same as 6 gallons of Morrison's very cheapest gas now.

That all sounds fine, but even with the second hand batteries listed that is about £8,000 worth - plus a cost for the electrical management and probably a regeneration braking system - let's call it £10,000 - which is far more that the RB is worth.

So, where am I going with this? The cost of batteries would make an EV conversion for the RB impractical at the moment, but I'm thinking that in 10 year's time that will decrease quite dramatically, and perhaps make this viable. At the same time 244 parts might be hard to come by, and the government may be frowning even more on people still running those filthy gas powered cars. The RB would (if my ballpark calculation of an electric motor fitting where the BW55 does now) make a pretty good candidate for conversion to an EV - if only the batteries were not impractically expensive.

Watch this column in 2030 for an update, I may just be finishing a Volvo 244 EV project; I can't help thinking that might be a really cool final chapter to the Royal Barge's lifetime :-)

PS. Spooky: someone has already tried:

https://cleantechnica.com/2018/06/02...fore-it-began/


... so, I've just finished reading the article, and the project would not be feasible in Denmark due to that country's bureaucracy - I'll do a bit of research and see if the chaps from Swansea would have such reservations here.

PPS. https://www.vice.com/en_us/article/v...-them-electric