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I'm converting my Mk6 back to reverse flow, I collected the rubber flap and front (Rad) blanking plate from Richard Banister today and as part of the conversion kit he had, he included an aluminium heat shield, pictured below. Does anyone know where this is meant o go? ps, sorry the picture is upside down, for some reason its getting inverted when I transfer the file

Success! Pulling the top forward as I lifted ensured that the bottom did not foul, thanks for all advice received

Hi, yes preparation done as you describe and I'm also using an engine hoist. I'll have another go today and if I still see the problem will try to photograph what I mean. Hopefully it was just me being over cautious

Yes, have pulled the top forward and have also removed the bottom plate. I'll have another go tomorrow and if I still have the problem will take a photo of it.

Hi Richard, well I must admit I thought it seemed odd but I seem unable to lift it up the inch or so that I need to. Is there a trick to getting it clear of the body?

I need to remove the radiator armour, I've removed all the bolts and it is free to move but it needs to move upwards about and inch or so to clear the bottom 'frame' part of the grill. The problem is that when I lift it, one of the captive nuts fouls with what I think is the radiator/fans mounting frame. Am I correct in saying this, does it mean that I need to remove the rad assembly or a least move it upwards before I can remove the armour? Why is nothing ever simple on a saracen?

Thanks Richard

Hi Richard, yes I had thought about simply removing the thermostat for test purposes......where do I find it?

I'll pull the plugs as it was running pretty roughly when I garaged it tonight. With regard the ballast resistors I think they are OK, I measured 11.7 volts at the coil (sw) when the ignition was on & engine not running

Thanks Clive, can you think of a failure mode that would only effect half the carb when hot? It's got to be an unusual one Nic

No, not replaced that yet, sort of assumed (bad idea!) that a hot cap must be better than a cold and possible damp one. But you're right it has to be a suspect

Hi Clive, so implicit in your question is that the carb is split in (two?) parts feeding 1-4 and 5-6 is that correct? I'm not that familiar with the layout of the carb. Since I assumed 1 & 2 would be representative of all 8, I did not look at the others (and they are less easy to get at at the side of the road when the engine is hot. Nic

Not getting anywhere fast here, no pun intended. Combined Ops Headcorn 2015 is not looking very promising! I removed the points today, cleaned and oiled the pivot and then went for my standard road test. 1.5 miles up to my house, let it stand for 20 minutes whilst I had a cup of tea then attempt restart and if all OK back to the barn where I keep it. It restarted reasonably OK and I did manage to drive it back straight away, but it was running very badly, spluttering, the odd backfire and were it not for the fact that it was down hill it would not have made it back, so problem still there; conclusion - it's not sticking points. I'm at a total loss knowing where to go now, this is a summary of what I have observed and done during the course of my testing. I should say that I don't check all the failure modes on each journey. I have fitted an in line (with the mechanical pump) double SU fuel pump which is located under the batteries. I have not particularly noticed it clicking away rapidly when I have the power loss problem - from this I conclude there is probably not a vapour lock in the fuel line After one of my journeys (when it would not restart/run properly) I cracked open the banjo on the carb, there was an escape of fuel - conclusion fuel was getting to the carb I am now running the Saracen with one of the beehives partially propped open to improve engine cooling After another journey when it would not restart I pulled plugs 1 and 2. Both were a nice light biscuit colour, both appeared to be dry. - conclusion, The engine was not running rich and flooding, the fact that I had been cranking the engine should I thought had meant that the plugs might have been damp with petrol. The fact they seemed dry made me wonder if the carb was supplying fuel to the engine or could it have been that the enginne being pretty warm that the fuel simply evaporated from the plugs? I changed the coil, no difference - conclusion either it was not the coil or the NOS coil had the same problem I changed the condenser, no difference - conclusion either it was not the condenser or the NOS condenser had the same problem I ran the engine from fresh fuel in a Jerry can, no difference - conclusion it is not a stale fuel problem On one of my test runs (this was on a coolish day) I measured the temp of the carb and felt it just to be sure. It was only around 30 degrees - conclusion it was unlikely that fuel was boiling in the float chamber. That said, other days the engine and carb have been very hot I removed and cleaned the points pivot, no difference - conclusion it is not points seizing as they get hot. When I consider what has been tested/changed, I don't think I can convincingly say that it must be fuel or must be electrical. I tend to think that it is a fuel problem but it may be dangerous to do so. So where do I go from here? It is the case that running reversed reverse flow cooling I have a non standard configuration and that this may be the problem. Certainly one of my next options is to convert it back. My only hesitation is that I think there might be a primary and secondary problem. It clearly does get hot on a hot day and reverting to reverse flow cooling will help this. But I get the feeling that a secondary problem is occurring which is causing my problems. The reason I say that it that following some of my tests the engine bay has just not been that hot, I'm sure a reversed flow Saracen having driven 10 or 20 miles would be a lot hotter than mine having just done 1.5 miles. So I'm now at the point where I think do I change to reverse flow cooling or perhaps I should fit a new carb (I did strip the carb a couple of years back) Nic

I wondered if it is worth pulling the points off the pivot pin so as to clean the pin or does this sound unnecessary. Hoping to have a go at it tomorrow

Thanks for the points suggestion, Richard Farrant has also raised that as a possibility. I'll take a look at them this week. it's only going to be possible to look at them when the engine is cold, hopefully I can get an indication of how tight they are. Nic

New coil and condenser made no difference. Tried running it direct from a jerry can of fresh fuel today to rule out fuel or fuel tank problems - no difference. On the last couple of test runs (my standard 2 mile run) I have been able to restart it, but it runs very roughly, there is no power and it is not drivable, again it is OK once left for an hour or so. Looking like the next step is converting back to reverse flow, so new fans and cowling :-(.

Thanks Clive I'm hoping to get to W&P and will certainly bring the parts if I come. Nic

Lots of good ideas thanks everyone and Clive thanks for the offer of testing my coil and condenser. Since Richard Banister is only a few miles up the road from me I bought a coil and condenser today. Coil is now fitted and hopefully I'll fit the condenser tomorrow and do another road test......I'll post results as soon as I have some Nic

Hi Phil, IR thermometer is a good idea, I do have one which I'll need to check out first but it could yield some interesting info. The spark idea is a good one, but difficult to implement when there is only one person. I think the fuel should be OK as I put fresh in this year and also when it's running, it runs really well. I've got to resolve this issue as I have spent two hard years restoring it cosmetically inside and out and sitting in the garage is not what I want it to be doing. Nic

Hi Richard, no not changed them yet. I think until today I had really assumed that the problem was fuel starvation due to the points you make and was focused on ways to mitigate, ie adding in an additional electric fuel pump. I can imagine that I will end up changing the fans and replacing the cowl, but perhaps do the other things first ad they are pretty quick to do Nic

Hi Richard, I appreciate the point you are making and this morning I spoke to Richard Banister about buying one of his reverse flow cooling conversion kits. However........ Before making the decision to buy and fit this I conducted a fairly controlled road test today. As I say I propped open a beehive and this really did allow the engine bay to vent and stay pretty cool I also have the vents open inside the vehicle which do allow air to vent from the rear of the gearbox. I drove less than two miles when I stopped the vehicle which was running smoothly. As usual it would not restart, I immediately was able to confirm that there was fuel at the carb and there were no vapour locks in the line. The carb was only warm to the touch I simply cannot believe that vapour locks/boiling fuel in the carb could have been a problem today. I am however convinced that the problem in in some way heat related as by allowing everything to cool off resolves the problem. I'm not saying that my cooling configuration will not cause problems on a hot day and a 'long' journey, but today the temperature of the engine etc was just not that hot. Not sure what the cost of a condenser and coil is, but my thoughts are that it might be worth me swapping those out first before I change fans and re-instate the cowl.

That's intersting and I'd not considered it, so your problem was also heat related and presumably would do it every time you used the vehicle?

Some background - My Mk6 has been converted to conventional (non reverse flow) rad fans, so sucks in at the front and vents through the beehives. The problem I have is that is starts and runs fine for a few miles, but if I come to a standstill the engine may then stall, or even if I stop the engine which has been running perfectly up to the point that I stop it, I cannot restart the engine for an hour or so until it cools down. Yes I know I could convert back to reverse flow, but this is a fair cost and effort to do (as I don't have the parts) and I'm not 100% convinced that it will solve the problem. I have been working on the assumption that the fuel line or carb was getting a vapour lock so I fitted a secondary electric fuel pump to push the fuel through - problem not fixed. Today I propped open a beehive and drove the vehicle a couple of miles before stopping, as usual it would not restart. Now the relevant points are: the engine bay and carb was not that hot, so I really don't think it was boiling fuel in the carb (one of my theories) the electric pump was not ticking away, so I believe there was fuel in the the lines, in fact when I loosened the banjo on the carb there was some pressure in the lines and I got a squirt of fuel the water temp gauge was reading normal temperature and nothing was boiling over From this I conclude that it is perhaps not a fuelling problem. Next thoughts are (a) the ignition condenser or (b) the ignition coil are breaking down when they get hot. So any thoughts, could this be an electrical problem when it gets hot? any easy quick tests that I can apply at the side of the road, so there will only be me there meaning I can't crank the engine and have my head in the engine bay at the same time so limited as to what I can easily do. Nic ps I've only got just over a month to resolve this if I'm to get to Combined Ops at Headcorn this year.

Thanks Terry, have just been to my Saracen and photographed the gearbox and can see the dipstick as shown in your photo, I think I was being fooled because I was looking for a dipstick (handle) as shown in the manual. Was reluctant to unscrew things in ignorance in case spring flew out never to be in again. Nic

You're dead right, that is exactly as my manual describes it but there was no dipstick on my gearbox and no obvious missing dipstick either (unless I'm going mad). I'll take a photo of it today