745 GL - Carb or injection?
 

Dear all

I have recently acquired a lovely 1991 745 GL from a friend of my granddads, who sadly passed away earlier this year. He essentially owned the car from new, took very good care of it, and it has the fattest service history file I have ever received with a car before. As a result, I am keen to continue taking good care of it, and learn a bit more about the car.

I understand that it had a webber carb conversion carried out in 1995 (which cost around £300 at the time according to a receipt I just found). I was just wondering if anyone could tell me why he might have done that, and whether the swap would have been in place of the original carb, or if it should have come with fuel injection from the factory.

The car runs very well, and seems to return ok mpg considering, though it is a fair bit slower than I was expecting if I'm honest (the small diesel vans I drive for work feel surprisingly peppy in comparison...is that normal)

Any opinions on whether to change it or not would be much appreciated. This car is actually a year older than I am, so I can't say I'm an expert when it comes to carburettors. I do have a bit of mechanical knowledge though, having completed a turbo conversion on a mk1 mx5

Best wishes
Alex

I had a 1986 740 estate with B230K Engine like yours.

We were having running and stalling issues with it after a year and Volvo diagnosed the pierberg 2B5 carb was the cause. Volvo wanted stupid money so asked an independent garage to fit our supplied Webber manual choke conversion kit. The Pierberg 2B5 carb apparently used to give problems.

Garage fitted new Webber carb and still cutting out! Said they would look for the issue and phone back.

60 minutes later, said your fuel pump relay is fubar, fitted new one and all working. When at Volvo, I had asked if the car had a fuel pump relay to be told "no, just a fuel pump fuse!

Moral of the story, cost £400 to sort a £20 part!

A few years later the webber carb jets would block up even with 2 inline fuel filters. You could drive hours then spluttering and rev counter bouncing up to 3k rpm. Pull over, blow the jets out and all good rest of the journey.

Started to get worse over time. Decided as we lived in rural France, to buy a New Toyota Corolla. While we waited 2 weeks for the new car it drove and worked faultless! The last issue may of been electrical.

My next Volvo was A 1989 240GLT with Mechanical D Jet Injection. Had no issues in the 10 years I had it. Now have a 1996 940 LPT turbo, again no issues.

Others on here have the B230K carb and not had any issues.

I actually found the Weber conversion kit better than the Pierberg and seemed to pull very well in 3rd up a hill.

Give it a good service. Plugs, Distributor cap, rotor arm, probably rev limiting one. Good quality Bougicord HT leads. I used NGK plugs, can't remember the code.

Is the Cambelt recent within 5 years old/ 50,000 miles? Suggest genuine Volvo belt as cheap and tensioner. The B230K is an interference engine. Ie bends rods if cambelt goes. Labour at garage should cost 2-3 hours taking their time.

Also renew the green fuel pump relay, behind ashtray.

James:thumbs_up:

Be aware that the B230K was a one-year only model; if the timing belt does go and damage a piston you'll probably struggle to find replacements; a friend of mine had the belt go on his, and the belt neither hadn't done a high mileage nor was particularly old. He was lucky that it went at low engine revs but still bent valves. The tensioner will only need relacing if it won't spin easily or makes horrible noises when spun, otherwise they last for eons.

It's a shame that your '91 745 GL didn't have Bosch LH2.4 injection which was introduced a model year eariler in Jan 1990 as a free option.

'91 was at the very end of the switch over to the 940 designation. I assume it had a BxxxE engine which even in 1990 were being knocked out at a bargain basement price.

I would be interested in seeing a picture of the under bonnet if you can post one and, knowing what the original engine designation is on the white sticker on the top of the cambelt cover or even the 4th and 5th numbers (engine designation) in the VIN code after YV1.

Cheers, Bob :)

The performance sounds about average for a B230K with a carb, the Weber as James has pointed out was the "go to fix" to sort the awful Pierbug (yes i know it's Pierburg, think why i changed it) and if it's working well, i'd leave it alone, just routine servicing using NGK plugs, Volvo oil filter, semi-synthetic 10W40 oil and make sure you change the timing belt and tensioner as advised - if in doubt, change the tensioner as being a B230K, it is an interference engine.




Just FYI James, you had K-Jet - D-Jet was a very early electronic system in the late 60s/early70s, very similar to the L/LE Jetronic of the early 80s. Also the fuel pump relay might be white, same as the K-Jets used.

Spark plugs if memory serves are NGK BPR5ES on the carb, i can double check though.

Not sure why I said D jet. As you say K jet.

James.:thumbs_up:

Surely a 1991 740 shouldn't have a carb, where they not replaced with K-Jet in 1988 MY?

As far as i always knew, the GLE was the only one with K-Jet, this one is simply a GL so would almost certainly have the B230K carb engine.

Mine is an SE 88MY with K-Jet, also owned a few GL's with K-Jet

They were still making 340s with carbs in 1991. 1993 was the year Cats and injection basically became a requirement. Injection was a sports options up to then.