Filter head

gmctd · **Posted:** Sun Sep 21, 2014 3:55 am

Activation temperature would not be of consequence, except for a fact any 5th grade science student knows: liquids congregate at the lowest point in any system, while air congregates in the highest point - with the filter head being the highest point in the KJ system, and the heater being the highest point in the filter head, any heater operation will most invariably commence in air, rather than submersed in fuel - and since it is nothing more than a series of solid-state "coins" compressed together, it doesn't take much to overheat with resultant damage to the plastic connector - colder climes would necessitate replacement to the upgraded version, sooner rather than later.

The glow plugs activate on each start cycle, on-time set by coolant temperature - summer ambients or warm coolant temps call for very brief on-time, cold temps call for more on-time

The NOOB guide at the top of the KJ CRD section lists a website where the Factory Service Manuals can be downloaded in PDF form, with full service procedures including procedure for checking glow plug continuity - briefly, there is a gray 4-wire connector coming from beneath the intake manifold - disconnect it, use an ohmmeter in the low 2ohm range, measure between engine ground and each of the 4 pins for less than 0.6 ohms, indicating a functional glow plug - they are 7-volt ceramic units, so do not attempt any direct testing with 12 volts

rancherman · **Posted:** Sun Sep 21, 2014 9:44 am

gmctd wrote:

Activation temperature would not be of consequence, except for a fact any 5th grade science student knows: liquids congregate at the lowest point in any system, while air congregates in the highest point - with the filter head being the highest point in the KJ system, and the heater being the highest point in the filter head, any heater operation will most invariably commence in air, rather than submersed in fuel - and since it is nothing more than a series of solid-state "coins" compressed together, it doesn't take much to overheat with resultant damage to the plastic connector - colder climes would necessitate replacement to the upgraded version, sooner rather than later.

The glow plugs activate on each start cycle, on-time set by coolant temperature - summer ambients or warm coolant temps call for very brief on-time, cold temps call for more on-time

The NOOB guide at the top of the KJ CRD section lists a website where the Factory Service Manuals can be downloaded in PDF form, with full service procedures including procedure for checking glow plug continuity - briefly, there is a gray 4-wire connector coming from beneath the intake manifold - disconnect it, use an ohmmeter in the low 2ohm range, measure between engine ground and each of the 4 pins for less than 0.6 ohms, indicating a functional glow plug - they are 7-volt ceramic units, so do not attempt any direct testing with 12 volts

Yep, just as I suspected. My 6th grade education finally paid off! :pepper:

Thanks!
On the start sequence, when you turn the key, there is a brief hesitation before the starter 'hits'. is that time when the glowplugs are cooking? And when it's sub zero, one should expect a several second delay?
I have a Bobcat skidsteer, with Kubota diesel.. ya turn the key, and the screen will tell you to 'wait' X seconds until good-to-start. Sometimes 20 seconds is reqd.

papaindigo · **Posted:** Sun Sep 21, 2014 10:00 am

The 06 FSM pgs 8i-24&25 discuss the OEM 7v ceramic glow plug duty cycle. I presume it's the same for the Etecno1 7v's but how the OEM 5v metal glow plug cycle works I don't know, Keith at GDE probably does.

Ideally you should wait to start until the glow plug light goes out which the Owner's Manual says is a maximum of 2 seconds. Given N. FL temps mine stays on so briefly as not to be noticed even down to 18F.

In colder areas, say below 0F, I'd expect "cranky" starts with rough idle and some smoke before things start to settle down. This can be avoided to a certain extent by using the block heater either overnight in extreme cold or on a timer set for 2-3 hrs before startup. If you use the block heater remember it does not heat the transmission, transfer case or differential fluids so be gentle on your drive train for the first few miles. In fact the tranny won't even go into upper gears until its fluid warms up.

lacabrera · **Posted:** Sun Sep 21, 2014 12:27 pm

rancherman wrote:

My new-to-me 2006 crd was a deeeep south texas vehicle... now residing much closer to the Arctic circle!
What is the threshold when the fuel heater kicks in? Mine still has the original small plug filter head, and was wondering if cold climates, hence more fuel heating, was causing the plug area to degrade?
I plan on changing it out to the upgrade version soon.
Same questions with the glow plugs too.. what is the theory on 'when they activate'. Is it every start cycle? or only when it's a certain temp?

I read some were that the fuel heater kicks in when fuel temp is 7degree c or below. Forgotten what temp it shuts off.

WWDiesel · **Posted:** Sun Sep 21, 2014 1:05 pm

gmctd wrote:

The poly thermo-plastic tubing fuel lines are copied from Ford, with their German Ford\MAZDA associations, all well and good for pressurized low-pressure fuel systems, but problematic in remote-mounted pump, draw-type systems - which the KJ CRD is one of...................................

Thus, my continued recommendation of intank pump or close-mounted inline pump near the fuel tank, whether plastic or clamped rubber fuel line connection(s)

If you go the in-tank pump route, no changes to the fuel line quick connectors are required due to the whole system being a 14 psig pressured system. Any leaks of any kind, at any fitting or location would show up very quickly. And as gmctd stated, the fittings are designed for pressured systems, not suction type systems. :wink:

Just think, a little over 20 years ago, most all gas fuel systems used the suction method with the mechanical fuel pump being mounted on the motor and it sucked fuel from the tank all the way to the motor. Back then, you never seen any such things as quick connects, everything was metal tubing with rubber hose at all flex points and everything was CLAMPED with some kind of mechanical clamp, be it screw type or crimp type.... :roll:

lacabrera · **Posted:** Sun Sep 21, 2014 3:15 pm

I have had a good look around the hoses near the fuel tank, I am 99% sure one of the quick connect connections is letting air in. All is as it left the factory with no sign of damage etc. I am bleeding air from the filter head every couple days even after blocking the leak at the head. I can tell that a previous owner has tried to sort the problem before by fitting a non return valve just before the filter. I suppose it helped stopping the fuel returning back to the tank over night.
Just ordered all parts for an in tank lift pump installation and replace the cr_p quick connect hoses.

lacabrera · **Posted:** Sun Sep 21, 2014 3:23 pm

Just a note. If the quick connect connections are like push fit plumbing fittings which tighten on pressure, What happens with Negative pressure (vacuum) ? food for thought? :banghead:

thermorex · **Posted:** Sun Sep 21, 2014 5:26 pm

lacabrera wrote:

Just a note. If the quick connect connections are like push fit plumbing fittings which tighten on pressure, What happens with Negative pressure (vacuum) ? food for thought? :banghead:

I think you answered this question yourself already, lol, by bleeding the fuel filter every so many days. Very bad design for a non in tank pump system...

rancherman · **Posted:** Sun Sep 21, 2014 10:35 pm

lacabrera wrote:

rancherman wrote:

My new-to-me 2006 crd was a deeeep south texas vehicle... now residing much closer to the Arctic circle!
What is the threshold when the fuel heater kicks in? Mine still has the original small plug filter head, and was wondering if cold climates, hence more fuel heating, was causing the plug area to degrade?
I plan on changing it out to the upgrade version soon.
Same questions with the glow plugs too.. what is the theory on 'when they activate'. Is it every start cycle? or only when it's a certain temp?

I read some were that the fuel heater kicks in when fuel temp is 7degree c or below. Forgotten what temp it shuts off.

Thank You! I suspected somewhere around 40f... close enough! I'd bet my San Antonio KJ never even been energized. Probably why the original FH is still onboard

ATXKJ · **Posted:** Mon Sep 22, 2014 8:48 pm

I will add the caveat - the in tank pump will Not fix bad tank connectors - been there - done that.

while you're dropping the tank- fix the connectors - it's pretty simple and easier than dropping the tank a second time.

lacabrera · **Posted:** Fri Oct 24, 2014 3:04 pm

Quick up date on the fuel filter head, Ditched the factory unit searched around on the internet and found one from Peugeot Boxer van/ Fiat Ducato van. These diesel vans are fitted with high pressure in tank fuel pumps and there filter heads that have a return back to tank connection plus the puck is identical to the 2nd generation Mopar one. No manual primer so less to go wrong (no longer required)
I know most here are fitting low pressure fuel pumps but here in Europe where 95% vans 4x4 etc run diesel, and if there have a in tank fuel pump there are all high pressure with a return back to tank. I understand this maybe of no use to most here but to let you know an alternative.

Filter head

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