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Hello everyone, I'm new to this forum thing, so please bear with us,
We've a T25 campervan which was a 1.7 Diesel Leisure drive 1989. I've just changed the engine for a 1.9Diesel from a Golf I bought. (the old one overheated and died) Got both engines out, bits swapped etc., new belts and oil pump, then fitted back in whilst off work for a week. The new engine is much better, less up and down gears etc., more torque.... very pleased. The new motors a real gem, no smoke , rattles, even starts first time. we've just been camping to Cornwall and put just over 1000 miles on it during a week and all's still good. The thing is, 50mph seems to be a comfortable cruise speed on the motorway. I fitted a VDO rev counter a few years ago and it seemed to be doing about 4200rpm. The van runs on Porsche Boxter wheels which on the rear are 225/50/16 which overall is a slightly smaller wheel/tyre than the original steel. Could this be the problem with my top end speed? or is it the high revving gearbox (original 5 speed 1989). Not sure weather to try bigger wheels or look for a different box. I'm not after doing 70-80, but 60 would be nice!
Any help appreciated.
put all your details in here http://westfield-world.com/gtc.html" onclick="window.open(this.href);return false; like tyre size, final drive of gearbox and gear ratios which you can get from here http://www.brick-yard.co.uk/VehicleSpec ... fo/gbx.htm" onclick="window.open(this.href);return false;
Then you can change the tyre size to standard and see what the rpms drop to. then try a slightly bigger tyre ect, hours of fun!
Think I'm going to have to get under the van and see if I can get the "actual code" off the box, not sure if its original. The build sticker under the dash says its a ABR box but these figures don't seem possible! I'm not sure if I'm been over cautious having just fitted the new engine (not wanting to blow it up) or the rev counter is reading wrong. as I remember there is a 3 way switch on the back of it, but I'm frightened of blowing another engine, It just seems quite LOUD
Hiya mate...
4200rpm @ 50mph sounds high...my petrol 2.1 with a 5 speed is doing less than 3,000rpm at that speed (2,900rpm perhaps)
The tyres you have are 3.33% smaller than standard so that definitely won't help, nevertheless, I can't see just over 3% making a 1200rpm difference? very strange....how accurate is the rev counter me thinks..
I don't have a rev counter but my 1Y purrs along nicely at 65mph with standard tires and 5 speed gearbox (was originally a JX engined setup, don't know what code box). It certainly isn't screaming it's t*ts off at 65.
We also have a problem with our top speed - drives comfortably at 50-55mph, can push 60mph but gets hot after a while, especially going up hill. When I bring the revs down (don't have a rev counter to check the rpm though) the temperature comes down too.
We have a 1990 T25 with a 1.9 Turbo Diesel engine fitted (from a VW Passat) before we bought it.
So we are wondering if there is a problem with the gear ratios as we believe there was a 1.6 diesel engine in it originally, or is something wrong with the coolant system (we recently replaced the header tank as there was a small leak, but the system is now sealed)?
I've got a 1Y running on a diesel 4 speed gearbox, standard wheels/tyres. Runs happily at 60 - 65, though the revs are high (no rev counter to know how high). This chart suggests that it will be 3635 rpm at 60mph:-
We also have a problem with our top speed - drives comfortably at 50-55mph, can push 60mph but gets hot after a while, especially going up hill. When I bring the revs down (don't have a rev counter to check the rpm though) the temperature comes down too.
We have a 1990 T25 with a 1.9 Turbo Diesel engine fitted (from a VW Passat) before we bought it.
So we are wondering if there is a problem with the gear ratios as we believe there was a 1.6 diesel engine in it originally, or is something wrong with the coolant system (we recently replaced the header tank as there was a small leak, but the system is now sealed)?
Thanks
Tracy & Andy
Hi, we think its to do with the gear ratios, ours runs at 50-55 like yours but there's loads more left under the right foot, it just sounds like it'll blow up if we push it any further. I thought of changing to bigger wheels to see if that would help but I'm not sure it'll give a big difference. Someone been kind enough to post details about the gearbox ratio's ( high revving ones coloured red). Think I'm going to look at that a bit more.
Temp on ours goes up a bit too when climbing but nothing major and then soon drops when on the level. Bleeding the cooling system is a nightmare but definitely pays off. You get alsorts of temp probs until you got all the air out.
Off in ours again for a week now, 2nd journey with the 1y engine so we'll see how it goes.
Hi, we think its to do with the gear ratios, ours runs at 50-55 like yours but there's loads more left under the right foot, it just sounds like it'll blow up if we push it any further. I thought of changing to bigger wheels to see if that would help but I'm not sure it'll give a big difference. Someone been kind enough to post details about the gearbox ratio's ( high revving ones coloured red). Think I'm going to look at that a bit more.
Temp on ours goes up a bit too when climbing but nothing major and then soon drops when on the level. Bleeding the cooling system is a nightmare but definitely pays off. You get alsorts of temp probs until you got all the air out.
Off in ours again for a week now, 2nd journey with the 1y engine so we'll see how it goes.[/quote]
Hey,
Thanks for the info.
It's an annoying problem and we are thankful that we aren't alone in finding a solution.
We have a problem with the bleed bolt on our radiator, which will not tighten or unscrew, so a good friend has suggested we get a new bolt or re-bore the radiator. That is something we are going to do soon. Then hopefully the cooling system can be bled properly, and maybe that will sort it?
Someone at a VW meeting mentioned about the gear ratios when we told him we had a different engine, so that got us thinking. The thing is, we are going to sound stupid here (well, this is our first T25 and we are learning!) but is there any way to change the ratios of the gears to accommodate the larger engine? If so, how is this done?
While we are on the dumb route we actually don't know what you mean by a 1Y engine conversion! Could you let us know what it means?
Enjoy your trip and good luck with the temperature.
Tracy&Andy wrote:
Someone at a VW meeting mentioned about the gear ratios when we told him we had a different engine, so that got us thinking. The thing is, we are going to sound stupid here (well, this is our first T25 and we are learning!) but is there any way to change the ratios of the gears to accommodate the larger engine? If so, how is this done?
While we are on the dumb route we actually don't know what you mean by a 1Y engine conversion! Could you let us know what it means?
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Yes it is possible to change the ratios in the box, but it matters what the gearbox is to begin with - this guy (also on here somewhere) will be able to advise you/ do it:- http://www.aidantalbot.com" onclick="window.open(this.href);return false;. You would need to get under the van and find the gearbox code to work out what type of gearbox you currently have.
A 1Y engine is a VW non-turbo 1.9 diesel engine that many people put in to replace a 1.6 non-turbo.
Former owner of 1983 DG panel van and 1983 Devon moonraker pop-top, 1.9 tdi (1z) conversion
Firstly, diesels can make a lot of induction noise, and this it can sound like the engine is revving its nuts off if the intake tract has not been properly engineered. If the inlet to the air filter has been carefully sealed and ducted from the original snorkel, the engine can be revving away and you will hardly notice it.
The original gearbox can probably be fitted with a longer (0.77) fourth gear, (available from Aidan) which drops the revs by 11% when cruising, but leaves the other gears the same for hill climbing. The 1Y engine should be well able to cope with this.
welcome to the joys of owning a diesel t25.
if you look on brickwerks site they do a ring and pinion set made speacially for turbo diesel engines there not cheap and your better off getting your gearbox reconditioned at the same time as having it fitted. looked into this myself but worked out quite expensive and the vw gearbox,s bearings arent big enough to cope with the amount of torque put out by turbo diesels (apparentley). also i found someone who does passat gearbox transplants but that was way out of my price league.
My ej22 sits at 3900rpm at 70 so yours does seem high. From what I have read the diesel models were geared high to make up for the lack of power. swap the box is best option. Im going to get aiden talbot to put a longer 4th and 5th in next year as will be much better for cruising. about 3000rpm at 70 would be nice. not cheap tho. quoted me 1k yikes
We went to get a puncture repaired and the guy there told us we had the wrong size tyres stretched over our rims, reducing the grip to the road.
We bought four proper sized tyres and the van drives so much better (glad it wasn't a sales scam!!!).
We also had a problem with our water level sensor in the water tank, which kept flashing on the dashboard, even though the tank was full. This also sent the engine temperature gauge higher than before (and the fuel level gauge read higher, too!) We changed that sensor and checked the wiring. There seems to be an electrical connection problem in the dashboard because I flashed my lights and the flashing water level started again (causing the engine heat gauge to give a higher reading again!), but stopped when I turned the headlights on!
Anyway, what I am trying to say is we can now drive at a constant 60mph, and even push 65+ when overtaking (down hill!) and keep a steady engine temperature (we drove the three hours to Busfest and the return journey, with no issues), without the costly process of changing gearbox/ratios. I will still probably save up for it, but thankfully there have been some less costly remedies.
Hope this is helpful, and thanks for all the help we received.
