TB Turbos of Lancaster

[gassygassy]

If you have been using motorhomes as long as I have you will remember TB Turbos of Lancaster who fitted turbos to standard motorhomes.

I have just bought an old 1999 AutoSleeper on a Transit, with a TB Turbo system fitted. I would have expected the camper to go a bit better than it does so I want to know if there is a way to tell if the turbo is working. Any ideas?

[Derek Uzzell]

Your 1999 motorhome (it would be useful to know which Auto-Sleepers model it is) would have been built on a Ford Transit Mk 5 rear-wheel-drive chassis with a 2.5litre diesel-fuelled motor.

The naturally-aspirated motor produced around 70PS, while the turbocharged version produced 100PS. (In 1998 an intercooled 115PS version became available, but Auto-Sleepers never fitted it.)

The Transit Mk 5 could be obtained with automatic transmission, but, in that case, Ford only used the naturally-aspirated 2.5litre motor. Performance was far from inspiring and it was quite common for larger/heavier Transit-based motorhomes with that specification to be fitted with a turbocharger conversion by TB Turbo.

I owned a 1996-built Herald Templar on a Transit Mk 5 RWD base that had the 100PS 2.5litre turbo motor and 5-speed manual transmission. I don't recall being able to hear the turbo spooling up, not there being any noticeable lag before the turbo started to provide significant boost. The motorhome was definitely no ball of fire, but performance was generally 'adequate' and what I expected.  

If your motorhome's turbo were genuinely not  working (ie. the turbo was not spinning) I suspect that the vehicle would be undrivable. Assuming that it is spinning, but the boost is sub-standard, check all the turbo hoses for splits through which high-pressure air could escape. Also check the condition of the vehicle's air-filter as, if it's dirty, air-flow to the turbo will be restricted.

This 2019 Ford Transit Forum discussion may be of interest

https://fordtransit.org/forum/viewtopic.php?f=4&t=195316

(I don't know what TB Turbo did to the Transit, but I'm pretty sure it did not involve taking the naturally-aspirated Ford motor and fully transforming it into the turbocharged version. So, if you've got problems with parts used uniquely in the TB Turbo conversion, diagnosis and repair may prove tricky.)

[Keithl]

I doubt that TB Turbos used any electronics back in the late 90's so the turbo is almost certainly mechanically controlled and the only way to know if it is working would be to add an old fashioned Boost gauge, either an old fashioned analogue gauge with a hose or a more modern electronic sensor and readout. Both versions would require either drilling and tapping into the manifold or adding a connection to a boost hose so neither will be that simple.

[Alanb]

My first thoughts aligned with those expressed above by Keith.  However you do not get more power just by blowing more air into the engine. You need to burn more fuel to get more power.  I am not familiar with older Ford engines, but on the Fiat 2.8idTD (pre 2000  and not electronically controlled) I believe that a Bosch VE style of pump was used.  This pump can have a "boost housing" fitted to one side of the pump, but it may have to be built that way, not modified. In one diagram that I have found, it seems that manifold pressure is used to increase the amount of fuel injected.

I think that the turbo wastegate on earlier engines served only to limit the maximum boost pressure. I have read reports of the wastegate linkage breaking on some Fiat engines.  This results in minimal boost.  Also if the boost pressure is sensed by the injection pump, then the connecting pipe could become detached.

I do not know what the complete modification made by Lancaster Turbos was, but perhaps the pump settings were only tweeked.  Replacing the pump would have been an expensive job.

To summarise, check that the wastgate linkage is intact, and check for any possible loose flexible pipes near the pump.  Also try boost pressure test guage as suggested by Keith.

The ultimate test would be a rolling road dynamometer, which I think Lancaster Turbos claimed to use, but I was not provded with any test results when I had an intercooler fitted to my Talbot Express.

Alan

[Derek Uzzell]

According to this 1987 article

https://archive.commercialmotor.com/article/2nd-may-1987/33/two-blows-for-power

the original TB Turbo conversion for a Ford Transit 2.5litre DI motor involved a Garrett/ AlResearch T25 turbocharger and increased power from 72PS to 95PS, and I'd expect that output to be much the same for a TB Turbo converted 1999 Transit.

This 2015 Ford Transit Forum thread discusses turbocharging a Transit 2.5litre DI motor and mentions the TB Turbo conversion in passing

https://fordtransit.org/forum/viewtopic.php?f=4&t=162905

The first thing for gassygassy to do is to check obvious things that would reduce the output of the motor (eg. air-filter condition and splits in the turbo hoses). After that, there's the matter of what " I would have expected the camper to go a bit better than it does" translates to. This is, after all, a 25-years-old engine and even when brand new the Ford turbocharged version had a relatively low power output. Then there's how much the exhaust and turbo manifolds are 'coked up' after a quarter-century (my Herald's exhaust used to smoke significantly under hard acceleration when cold).

Also, I note that (in 2020) gassygassy owned a Ford Transit-based 2009 Hobby T600 Siesta that (presumably) will have had a 2.2litre turbocharged motor. After the Herald I bought a new Ford Transit-based 2005 Hobby T600FC motorhome with 2.0litre turbocharged motor and this was MUCH livelier than the Herald. My Hobby's turbo was variable-geometry type and (as commonly happened) its operating mechanism jammed shut, causing a large and very noticeable fall off in power. The turbo in gassygassy's Auto-Sleepers motorhome will not be variable-geometry type, but if he's comparing the behaviour of the Auto-Sleepers with the Hobby's, there's no doubt that the former's performance (even in perfect condition) will be noticeably inferior to the Hobby's.

This 2005 forum discussion relates to a 1998 Peugeot Boxer-based Swift Royale motorhome with a 2.5litre motor.

https://forums.outandaboutlive.co.uk/topic/554-lazy-turbocharger/

and I notice that I said

It's quite common to be able to hear the turbocharger 'spool up' and, on diesels, this happens from quite low revs. (Certainly, on our Transit-based Herald, you could easily hear the turbo begin to whistle as it started to spin.) 

So, if the turbocharger in gassygassy's Auto-Sleepers remained completely noiseless when the motor was revved, it would probably be seized up. But (as I said above) if the turbo were inoperative, the vehicle's performance would be awful, not just a bit disappointing.