Fuel regulator solenoid Poor Starting when hot

[RichardM]

Greetings one and all (again).

Still suffering the no start when the engine is hot (normal running temp).

Swapped the fuel feed solenoid from my 'spare' parts Voyager. Started first time, took her for a run to warm her up, switched off, counted to 500 or so (cup of coffee actually), switched her on and up she fired. Delight, delight, delight. 

Set off for home, 4 miles later engine cuts out and won't start. 

Out with the cold start fired up and drove home only for her to die again as I was turning into the drive, managed to roll far enough to abandon her for an hour.

Went back started fine, parked her up the drive and went to bed.

Next morning started her up went for a nervous drive around the block, no problem.

Today drove to town, road works everywhere, nervously arrived in town half hour later. Bought the paint, went to start... nope... out with the ether, brum brum and drove home.

Now the question.. what the hell is wrong with her ??? Put your foot down and she rips through the revs like a banshee. Drives beautifully until she doesn't. Problem is I have no confidence in the reliability, especially when considering long journeys.

I am not convinced she isn't sucking air in somewhere but after new filter housing etc. I don't know.

Question 2 : Where is this air bleed valve (see attached of page [RG Diesel Supplement Page 14a.4..] do you have one ? Neither of the Voyagers I own have one. Does anyone have any idea how to check for air in the system?

With the new air filter housing I ca attempt to prime the line But it never seems to get hard enough to prevent further priming and, as the fuel system has ?? a non return valve feeding excess fuel back to the tank ?? I would not expect it to go rock solid .. should it ? aarrggghhhh.

Have a good day.

 

[bignev]

Hi mate!

I really wish I could help out on this, but as you know mine' petrol / LPG. But it really is ruddy mysterious!

A few years ago we had a Kia Sedona with the 2.9 diesel engine, and it wouldn't start hot after a while, but it never cut out. Blew black smoke when you booted it like a Klingon cloaking device though!! That turned out to be the injectors, I changed them myself, as the useless toads round here were "too busy" chicken more like.

My van had a non start problem when the non return valve failed, and if I primer pumped it while the Mrs wound it over it would start, but it had to be done at the same time - not prime then go to start it - that wouldn't do it.

However temperature was not relevant at all.

Edited August 6, 2022 by bignev

[RichardM]

Hi Nev, Booting mine just gives you a nice smile as it kicks up the road like a Porsche, (well almost), no smoke, no complaints... just that she sometimes throws a wobbler and dies for no reason at all.. tootling along at 40 and woops off she goes (bloody hard to stear when there's no power steering to help out!). I can live withthe hot no start - sort of but the dying with no warning is dangerous.

Ah well let's see what happens next. 

[bignev]

Yep it is indeed a dangerous possibility when they cut out with no warning. And yes, aren't modern cars bloody heavy on the steering with no assist!! As, of course, they are geared high to work with the hydraulic assistance, not like when we were boys - no assistance whatsoever, but geared low to be able to turn the bugger!!

My Subaru SOUNDS like a Porsche, well you know kinda, as it's got the same flat 6 engine. But nowt like the exhaust audio tuning sadly. 

[maxcaddy]

The traditional problem with starting after leaving it for some time was to do with the fuel system loosing pressure and needing repressuring. This isn't your case which you say is only when its hot, and once it's cold it's okay, consequently the question is what can affect the engine not to start when its hot ?.

That then gives you at least 2 likely routes, the first route is that there is a mechanical issue whereby for instance something gets hot like the cylinder head, and it fails to maintain compression. However if that were the case, I would expect a number of other symptoms like loss of water, overheating, lack of power, to show up long before it wouldn't start again. Most of any kind of that problem can be seen, smelt or heard, so it doesn't seem at all likely that route 1 is applicable.

Route 2 is that a sensor or electrical gismo is overheating and not working once it's been turned off. I.e something like a fuel pump relay that overheats and won't re-initialise again until the engine bay has cooled down. If possible, if you could track the location of such gismos i.e. crank sensor, injection cpu, some odd fuel related sensor, etc, it could be possible to identify a part that is very hot, and which could be the source of your problems. Noting that some electronic devices generate more than enough heat on their own, which a hot engine simply exacerbates.

All that said, what if after stopping when hot and failing to start, you poured/hosed cold water over the engine to see if by quickly reducing the temperate it provided an instant solution, and if so, then do it in a pattern of areas to pinpoint where the issue was ???

 

 

[RichardM]

I thought about the cooling scheme but in twenty feet of water... Have replaced most of the sensors to do with the fuel system and replaced the fuel bleed valve. Is it possible that the high pressure fuel rail that alledgedly has a non return valve built into it could cause the problem ?. I question most things in the ws manual having found too many anomalies to trust that the Yanks actually took any interest in the European build... Am currently trying to figure out how to build an air trap (as per the old diesel tractors) - finding space to do anything is a nightmare. 

[maxcaddy]

The question remains it only fails to start when hot. Fuel supply problems would surely be the same hot or cold ?

Back onto sensors etc, what if the key/ignition switch got hot and failed to function until it cooled down ?

 

[RichardM]

One quick (1/2 second) burst of cold start & she fires up straight away ..........?????????????????????????