trophy160

I was thinking about how I might improve the air flow through the engine bay and more to the point ensuring that any hot air at the back might be vented. The area above the fuel tank does link with the engine bay, if I opened these vents would it allow air from the back of the engine bay to vent?

Nic,

I remember one of the early private owners of a Saracen was one of our club members who had his own garage business. He had similar problems to you and fitted an electric pump near the changeover tap as the pipe work is accessible also it is easy to take a feed from the battery. He had a manual control, ie a switch by the pump that he could flick on when vapour locking occurred or the engine showed signs of faltering. Retaining the mechanical pump of course. The pump pushes the fuel through rather than the mechanical pump drawing it from the tank and an area where the vapour locks could be occurring. A relatively simple solution to his problem ...... maybe worth trying.

Hi Richard, that's got to be worth a go

I don't think there is going to be an immediate and/or simple answer to this problem and clearly I do need to prove exactly what the problem is, thanks for the various ideas suggested.

Perhaps I do have to reinstate full reverse flow but may try out one or two other things first. If I was to fit an electric pump up near the tank, I presume it can just be plumbed into the existing line, by which I mean leaving the mechanical pump in circuit, I can't think why I should not do this?

Thanks Clive,

 

I'd like to get a roll and redo all of mine eventually, but I think shipping will be a killer. What I really need though is some of the missing Kevlar bits, which it appears Nick has, if he wants to part with them.

 

Cheers,

Terry

If I have the bits you need, then you're welcome to them, but mine was not 100% complete so may not have the bits you need

Certainly a big improvement and a nice vehicle. I do have some questions and comments:

1) I would suggest reverting back to reverse flow cooling also. On the conventionally cooled Saracens, the majority of the engine heat is expelled through the armoured "trunks" that go under the side windows and these are not present on the RC models. I don't believe that the beehives are big enough or situated correctly to cool the engine alone; many people who have messed around with the cooling system on the Mk 3 and 6 have had similar problems to yours.

2) Whether you do restore your cooling system or not, you can probably improve reliability by fitting an electronic ignition kit and a LOW PRESSURE electric fuel pump. The pump especially helps with vapour lock. High pressure (fuel injection) pumps should never be fitted with carbies and can cause all sorts of problems, especially fires.

3) Your seat pads are incorrectly installed. The front edges of them should wrap around the seat lids with the corners held in the leather pockets.

4) Why have you removed half of the spall linings?

5) Why have you mounted a Bren gun? The Mk 5 and 6 never carried them.

6) Can you post up some details of your GPMG?

7) Can you post up details of your radio install, with lots of pictures please? I'm part way through a Clansman install myself and it would be great to see how you did yours.

 

Cheers,

Terry

1) Regarding the beehives, well clearly in the case of the reverse flow they did provide adequate 'cross section' to allow sufficient air to enter the engine bay and to be exhausted out from the radiator grill, so in principle when working in reverse direction the same air flow should be possible. I do not know exactly where the 'trunks' extract air from in the conventional set up but I presume it is from the rear of the engine bay? That being the case then air flow across the engine will be warmed air from the rad as must be the case with my set up. It does seem to me that some extra flow through the engine bay and out of the beehives (using some secondary fans) could well do the job and clearly be simpler and less costly than reverting to reverse flow.

2) yes, had certainly considered the electric pump up near the tank, electronic ignition perhaps but it start well and clearly not going the address overheating/vapour locks if indeed that is my problem

3) Thanks for that, didn't know that

4) the spall lining was in poor condition and anyway had to be removed to enable rust to be removed. Refitting the spall looked to be an extremely difficult job, not to mention where I would get replacement parts from that would match the rest of it. I thought long and hard about it and in the end decided to remove it, the remaining lining will also come out.

5) I know, but I like it and as noted there are other aspects of the vehicle that are not 100% original

6) Yes will do, it is a replica of course

7) yes will do, of course one could argue that like the Bren, the Clansman should not be fitted to a Saracen. I have not completed all the wiring yet, but will take a photo of the bracket I make up, once again non standard!

I bought my Saracen 15 months ago and during that time have being doing cosmetic restoration. Last summer it was sandblasting the exterior and spraying and for about the last 12 months I have laboriously been taking the interior back to metal and repainting. I still have one section left to do (right hand rear) but most of it is done. Along the way I have been buying Saracen 'bling' and most of that is now fitted.

I could not get to War and Peace because the driver's seat was away being refurbished, but have been getting it readied for the Headcorn Combined Opps. Last weekend I gave it a test drive but it seemed to foul its plugs. I fitted a new set on Friday and today took it for another drive. I drives really nicely for a couple of miles but then........the engine has a tendency to stop when the vehicle is stopped and it is then difficult to start and then only fires on 4 or 5 cylinders with no power. I think it is just the case that it is getting very hot (and it was a hot day) and it's getting vapour locks. If I leave it for a couple of hours then all seems well again. I should mention that it is reverse cooling Mk6 where someone has removed the cowling and put 'normal' direction fans on. But I guess it is struggling to get the heat out of the engine bay. I did notice that the deck around the bonnet area on the exhaust side was really hot after just a couple of miles.

Richard Farrant has suggested I might want to convert it back to conventional reverse flow set up, but I'm wondering before doing that, I try putting some extractor fans in the beehives to try to suck the hot air out of the engine bay - any comments?

My test runs caused chaos on my local country roads and it came really close to stopping in the middle of a single carriageway bridge, I just managed to get it over the bridge before it stopped.

Anyway, since it won't being going to Combined Opps, here are some photos of it before and after. You might notice that to to right of the right hand side fire extinguisher near the driver I have fitted my reversing camera screen and you can see my housing for the reversing camera where the tow hitch would go. I have to say this works brilliantly and was well worth the 40 or 50 quid from Ebay

Nic

Thanks Richard, that all makes very god sense

Thanks everyone for your help. I've pressurised my spare accumulator which looks like it has been rebuilt, to check that it holds pressure for a reasonable time. If it looks OK, I'll then swap this one out first. I'll take a peek under the check point caps tomorrow to see what sort of pipe I need to make up. Just one final question, is it always necessary to bleed air out? The reason for asking is that I was reading about changing accumulators on the Routemaster earlier today, I understand that it has a generally similar accumulator set up to the Saracen and the author commented that these were self bleeding in most instances.

Hi mate

I'm a hydraulics engineer, depends on your system. Most modern one's are self bleeding, just run them up for 5 min to warm up and get things circulating then operate slowly. What does that system control?

Is it a Single Acting system or Double Acting? Ie . . Brakes are single acting ( no return to tank line, just primary pressure line) or wheel drive motor will be double acting Bi-Directional, meaning it can move in both directions.

Does it operate a hydraulic cylinder or drive motor?

 

Paul

Hi Paul,

All I can tell you is that there are three circuits (accumulators) two of them are for brakes and the third is for steering. I have attached the hydraulics schematic here, not sure if there is enough information for your question to be answered.

Right, I've got my cylinder of nitrogen, regulator and a spare accumulator (plus seals to rebuild the others). I'm pretty sure I have at least two accumulators that don't hold pressure that long so I want to swap one with my spare and remove/refurbish the other one.

My question asked in total ignorance is (once I have dropped pneumatic and hydraulic pressures) when I swap out an accumulator, i.e. broken into the hydraulic system do I then have to bleed the hydraulics to that accumulator. Sorry if it is a really dumb question.

thanks

Nic

Thanks Terry, well here is the next question in fact there is a second related question.

1. When I swap out an accumulator I am braking into a hydraulic system, where do I need to bleed the system?

2. I may be needing to change brakes hoses to the wheel cylinders, what is the procedure for brake bleeding

When I bought my Saracen I got a spare accumulator with it. It is clearly not new, but looks like it might be reconditioned as it has a plastic blanking plug fitted in the hydraulic end. Would it be OK to charge this up off the vehicle and to monitor if it holds pressure over time as a way of assessing it's condition, or would this not be advisable?

Just ordered myself a charging set today so I can rebuild my accumulators, having read all these horror stories I'm not sure I want to now !

OK, thanks for that. Did you find out how to remove them?

I'm trying to lube my suspension for the first time. So if I understand the manual correctly, there is:

[1] A nipple on the lower link bracket that lubricates the link pivots and shock absorber and bump and rebound damper mountings

[2] A nipple on the top of the swivel yoke that lubricates the outer pivots of the suspension links and the upper and lower pivots of the swivel yoke

[3] A nipple on the assembly bracket that lubricates the torsion bar sleeve etc

When I pumped oil into [1], I removed the blanking plug on the opposite end of the lower link and sure enough oil oozed out there OK.

Is there an associated blanking plug for [2]? When I pumped oil into this nipple it seeped out from an area directly adjacent to the nipple but not obviously from anywhere else, so how do I tell if the oil has reached the lower pivots and swivel yoke?

When I tired lubrication [3], I initially saw a build up of pressure at the rubber end cap on the torsion bar (which I then removed) but despite pumping more oil in nothing came out from that end cap area (as I believe it is meant to), but I could tell there was a lot of pressure between my oil gun and the nipple. I then tried removing the nipple to check if it was blocked only to find that the oil was under pressure and squidged out.

So my question is what an I doing wrong/how can I vent pressure as I inject the oil through the nipples [2] and [3] ?

I'm afraid I can't help with the answer, but if you know where I can get hold of a NOS vision block I would be most interested to hear.

Nic

Thanks, Richard Banister says he's getting some in so should be OK

Anyone know what thread (+size) the grease nipples will be for the Saracen?

Not sure on the Cheiftan fitment, but if the valve is standard car tyre valve type, then yup, it should work. Got mine from Ebay, some chap in America selling them for filling up gas shockers.

 

http://www.ebay.co.uk/itm/Nitrogen-regulator-king-fox-air-shock-w-no-loss-chuck-NAL-CHUCK-FILL-VALVE-/160758079931?pt=Motors_Automotive_Tools&hash=item256deda1bb

Was just about to order one of these off Ebay but saw the comment about different cylinder fitting for different countries. Did this work OK with 'UK' cylinders?

Cost of seals works out roughly £60 per accumulator.

 

Simon

Hi Simon, I better invest in a set (X3) as I'm bound to need them someday. Please let me know how much and how you would like payment

Nic

I'm most grateful to all replies which are really helpful, it looks like I have a choice of where to stow it.

thanks again

Nic

Hi, I've been trying to find some reference to Bren gun storage brackets for my Saracen. I just came across this photo, are the brackets I have ringed Bren gun storage brackets by any chance?

Thanks Ian

I appreciate such a knowledgeable response, it's nice to better understand what was installed in practice.

I will either fit 2 X 353 or one 353 plus DMU into my Saracen as I have these units (yes, I know probably not totally original). If I fit the DMU then really I would like it to be complete hence need what I believe is called the BID 250 unit. Is it unrealistic to think I can get hold of one of these?