My project is a 73 144 (B20A) BW35 in Orange.
I've recently acquired a 74 144 (B20A) as a parts car and it has the M40 manual transmission. Unfortunately this cars body is too far gone to be salvageable but it runs and drives well.
I've done a bit of research on the forums and it seems to be relatively straightforward as far as trans swaps go. Ive never attempted a job of this size but thought it an ideal learning opportunity and have a few questions before I start.

1. Would it be a huge advantage to remove both engines and trans while connected and do the swap outside of the car? or should I attempt to leave the engines in and just drop the gearboxes?. Keep in mind I only have ramps and would need to borrow/hire an engine lift.

2. Besides the clutch kit, is there anything else I should be replacing while I'm there? gaskets etc.

3. Last time the shop replaced the clutch in my 245 they had the flywheel machined. Will I need to have this done or does it depend on its condition?

Thanks for your help.
Welcome!
Love that orange! I had a BMW 2002ti in same colour.

You may as well .machine and replace all seals while in there , saves a headache later.

You could sell parts off the donor if you are not saving them yourself.
L.

Machining the flywheel is not essential, but is good practice to avoid shuddering or other dramas with the new clutch. The cost is minimal compared to the time/effort of removing and refitting the gearbox.

When the box is out, have a close look at the rear main seal for leaks. Again, there's never an easier time to replace the rear main than when the box and flywheel are already off the motor.

I'd suggest that the effort in removing the motor is greater than the extra hassle of doing the conversion with the motor in the car. If the rear main seal is leaking, then it probably is worth removing the motor.

Another thought: the 74 should have a twin carb B20B motor, compared to your current single carb B20A. The B20B also has a larger cam and higher compression ratio. The 1974 model should also have bigger valves. All of these add up to a worthwhile power increase.
If it was mine, I would be looking to swap the motor as well.
Spac;70349 wrote Another thought: the 74 should have a twin carb B20B motor, compared to your current single carb B20A. The B20B also has a larger cam and higher compression ratio. The 1974 model should also have bigger valves. All of these add up to a worthwhile power increase.
If it was mine, I would be looking to swap the motor as well.
Interesting, I haven't actually picked up the manual car yet but it had a single carb (I assumed to be a Stromberg) when I looked at it. Strangely it did have the twin carb airbox - I assumed Volvo must have adapted it to fit, but maybe this engine has been converted to a single carb at some stage. The other reason I assumed it was a B20A is because it shares the same engine code on the vin with the orange car (1=B20A according to this page) but not sure how accurate that is.

I do have a twin carb manifold in the shed that came with some parts, but not sure if its for SU's or Strombergs, or if that even matters. Will pick up the car this Friday and report back.
Interesting. Maybe the "manual = twin carb, auto = single carb" rule doesn't hold for the very late 140s. If so, I apologise for wrong info!

Strombergs and SUs use the same manifold.

The twin carb exhaust manifold has two outlets, the single carb one has only one (remembering that the intake and exhaust manifolds are integral).
Would be better with Webers wouldnt it?
Put a new pilot bearing in while it's all apart.
Less than $20
Also check the trans mount. Often old ones are oil damaged and turning into jelly.
Easy to add a new one while it's out.
6 days later
Ex850R;70367 wroteWould be better with Webers wouldnt it?
Of course however I would like to the spend on this build as low as possible (As I have a 245 to restore also) and I have 2 x Stromberg Carbs, the manifold required and the airbox. I may just need to fabricate the linkage, or find a second-hand one.

Got the car home on Friday and gave it a quick wash to make disassembly a bit nicer. It appears to be the B20A but with the B20B airbox with a single hole. Strange.



I will strip this car and save the parts I want, including the engine. The current plan is hire a lift to get the engine and trans out of the donor car, and swap the BW35 out in the orange car with the engine in place with new clutch, pilot bearing, release bearing and gearbox mount. Will asses the rear crankshaft seal when I get there. Wish me luck. Will probably have a few questions along the way.



Welcome. What an awesome pair of motor cars you have, but I must confess bias in that regard.

Yes, that's a B20B air cleaner in the yellow car, and that setup on a single carb isn't factory***. If that yellow 144 is type 1443349A, he's a 74 model which originally left the assembly plant in Melbourne with a B20B and M40. Many strange things could have happened in the following 42 years. Xoe, my 142, also had a B20B and M40 at 'birth', but got converted to an auto and B20A sometime after leaving the plant with the good gear originally, so it happens.

The other guys have covered nearly everything, but just thought I'd throw these things into the mix.

It's worth noting that 73 model engines have a six-bolt flywheel and 74 models have an 8-bolt flywheel. The 74 model oil seals on the timing gear cover and rear main oil seal are superior (IMO) to the felt things on earlier engines.

The tailshafts should both be of the 1310 type. It's worth checking the condition of the centre bearing and the support rubber while you're in there and at it.

The condition of the clutch cable is worth examining closely. When (not if, when) they snap, it is always suddenly, without warning, and at the most inconvenient and inopportune times. If you can put a new one in, it's recommended.

Do you have the Volvo Greenbooks and parts manuals? They pretty much take the guesswork out of the exercise.

If you're thinking of doing a rebuild, B20 engines are hard to get wrong. The 1800 crowd, who want to keep their cars original, have ensured that engine components are still around and plentiful.

Oh, and good luck.

*** EDIT: wrong; see below
Thanks so much, this is exactly the type of info I was looking for.

The Yellow 144 has the Vin 1441342A suggesting its a B20A, standard body, M40, RHD (Sweden) and a 1974 model but yes, anything could have happened in its history.

I should probably mention I am in New Zealand, and we tend to have a real mixed bag of privately imported Volvos, My 1976 245 is ex Singapore with a B21A with an M45, and I also owned a 1989 245 from the UK with a B230E and K-jet (M47). Trying to buy parts for these cars has been challenging.
I have been concerned about the flywheel, but couldn't find any solid information on when the change happened however I did read today on brickboard a way to determine which crankshaft is in your B20 is to check the size of crankshaft pulley bolt. If the bolt uses a 13/16" socket/wrench, you have a 6 bolt crankshaft. If the bolt uses a 7/8" socket/wrench, then you have a 8 bolt crankshaft. Can anyone confirm this?

I have added the driveshaft center carrier support mount, bearing and clutch cable to my list of things to order from FCP, mainly to avoid paying for several lots of shipping if I find out I need them.

I have found the green books online, and have the Haynes manual.

Im planning on putting the spare B20 on a stand and re building as time and money allows, perhaps its better if the orange car (Mandy the Mandarin) will remain an auto until this is completed so I can swap in the rebuilt engine and m40 together.


Every day with an auto is an extra day deducted from your lifespan.

Measured the crankshaft pulley bolts last night and sure enough Mandy has a 13/16" and the yellow car has a 7/8" bolt. Hmmmmm. Back to the drawing board.

I had a closer look at the air filter housing, appears to be factory.



Heres the twin carb air box:


My mood:





Never seen an airbox like that!
Very interesting. I'll hazard a guess that there was a shortage of single carb airboxes on the production line and they adapted twin carb ones for a while.
@Jeezy I'd pull engines. It's super easy and 100% less swearing.
Jeezy;70805 wrote I had a closer look at the air filter housing, appears to be factory.
I sit corrected. It is factory, the EEC version of the B20A air cleaner on late production, and like Spac, I've never seen one before either.
10 days later
I'm constantly amazed at all the differences between the years. I removed the rear springs from the yellow car with the intention of swapping them for the sagging ones in the orange car however it looks like they are different (73 is pigtail at both ends and 74 is pigtail at the bottom and open at the top).

Will the upper perch from the the 74 bolt in to the 73 and allow me to install the 74's springs?

Yes.
I've not seen double pig tails one a 73 before - I assume this means your 73 was converted to the older type in the past.
The parts manual lists two options for rear spring mounting.
It could be an early 73?

Definitely look into swapping the motor and changing cams over. Having just done a heap of research, su's are fine up to 120rwhp and more before they cause issues. There are more modern camshafy designs around and they do not cause a horrible idle that upsets the carbs as much. It's just there are that many its hard to say which one to go With.

Compression test both motors which should help your decision.
© 2013-2023 Oz Volvo. All rights reserved. | Forum Rules | Privacy Policy