SD33 starting problem

[RMP&O]

So I have a N/A SD33 in my 1983 MQ Patrol, it is on 24v. Last month while on a week long 4wd trip she failed to start n the last morning. After checking voltage and ohms we found out glow plugs were shot. We were able to start the truck with a shot of starting fluid so we could finish the last day and get out of the mountains.

I recently put in new 24v glow plugs which are working fine and getting the correct volatge. They are set up on a push button so the auto glow plug timer is not in this truck. After doing this I still can't get the truck started so I started trouble shooting other things. She is getting fuel to run so it isn't a fuel delivery problem. Air intake is fine and clean so has plenty of air. Truck runs good when I get it started so it isn't a compression problem.

What I have figured out is the injection pump controller is not moving to the start position when the key is turned on. It does however go to the run position and also to stop when the key is turned off. I even checked voltage and ohms to/at the controller and it is fine. So I think ok, controller is toasted. This leads me to think I can start the truck by moving the governor to the start position and the truck will start. So I get a friend to help me, we glow the truck and I know glows are hot enough to start it, I move the governor to the start position, he turns it over and nothing. It just cranks over and doesn't even try to fire up.

I can start the truck very easy if I glow it the right amount of time and then shoot a tiny little shot of starting fluid into the intake. I know this is bad, real bad and I shouldn't do it. Trust me I am using the smallest amount of fluid possible and only doing it when I have to. But there is no other way to currently start the truck.

So does this mean my 25year old pump controller and governor are shot? If I put the governor in the start position but the truck won't start this must mean it is not supplying the "excessive fuel for starting" as per the Nissan manual? This is a very simple motor, I clearly understand it but am I missing something here to trouble shoot?

Never had a problem like this before only bad plugs or injectors. The truck ran and started fine up to the last day of the 4wd trip. Any help would be great before I source expensive parts....sorry for long post but I always feel the most amount of info is the best!

[pongo]

it prob wont help But,

If i run to thick a mix of vege oil it wont start, But needs a spray of hair spray to fire.

My injector controller only works on start and stop though,

It should stills tart if on start or even run me thinks, as the older versions and newer models have been converted to cable start and stop when the controller shits itself.

Did you get fuel from a different servo ? maybe gelling, etc.

good luck and keep us informed

[N2O]

maybe you should install 23V glow plugs ? (there were 23V and 24V models of glow plugs)

[V8Patrol]

Truck runs good when I get it started so it isn't a compression problem.

Giday Ian...... long time no chat

You know better that that, get a leakdown test done for a REAL compression test


Does she sound like she's dieseling up when you get her started ???
if so old age and therefore low compression may be the cause.


Kingy

[rickzta]

Its gonna sound very simple but check your oil level....

a mate had the issues with not starting, added 2 litres of oil and bang, it kicked over...

the Nissan manual said there is a oil pressure switch that when oil level/pressure gets low it will shut off...

sounds simple but only a suggestion...

Cheers

Ricky

[RMP&O]

Truck runs good when I get it started so it isn't a compression problem.

Giday Ian...... long time no chat

You know better that that, get a leakdown test done for a REAL compression test


Does she sound like she's dieseling up when you get her started ???
if so old age and therefore low compression may be the cause.


Kingy

Hey Kingy! Ya I suppose I should stop assuming and just find out for sure. It is kind of a pain to test compression on the SD33 for all cylinders since the pump is in the way. But I suppose I could do the oil trick, ya? I just don't think it is compression since she runs so well once I get it running!

The plugs are 23.9v and I have 23.4-23.9 at every plug. I haven't tested them on a battery yet to actually see them glow. Might try that just to be 110% sure it is not g/p. I did check resistance across them when I put them in, even though new and they were all good.

I will check the oil didn't know about that.

Fuel isn't gelling up as it isn't cold enough for that.

I have got some other suggestions from people too so will give it all a go this weekend. I am still pretty sure it is all in the controller and governor. I did run the controller with the rod unhooked form the governor and it does rotate when the key is turned off but not on. I know it used to do something before when key was turned on because you could hear it. Now it does nothing when key is turned on. Somebody said it is a very precise location that the arm on the governor has to be in for the "extra fueling" to take place. I didn't know that and was just pushing all the way to one side. So will play with it a bit more.

[V8Patrol]

Hey Kingy! Ya I suppose I should stop assuming and just find out for sure. It is kind of a pain to test compression on the SD33 for all cylinders since the pump is in the way. But I suppose I could do the oil trick, ya? I just don't think it is compression since she runs so well once I get it running!

Had a similar issue a year ago with a friends MQ SD33..... ended up being way down on compression yet once started it seemd fine and still drove well with no signs of being down on compression.
The give away was the dieseling up when you first started it.

We also found that this particular MQ would start with a trusty can of "Start Ya Bastard" ( starting fluid ) .... sound familiar ????



In the end we found that a double glow period worked

To do this.....

Glow the engine then crank it over for a very short turn
( IE: maybe 2 or 3 revolutions )
Turn the key off for 2 or 3 seconds
Re-glow the engine and then try and start it.

The additional glowing gets some extra heat in the cylinders and will help with the fireing up of the ole girl.

-----------------------------------------------------------------------------------


The pumps a re almost bullet proof on the MQ's, so I doubt that its a pump or actuator issue..... but having said that ...... it may well be an electrical controling issue thats related. Try the relays, connectors, and motor that control the actuator arm.
An old relay may not be playing the game and giving you full throw on the rod ( motor)

Later mate

[84mksd33t]

V8Patrol: I do this all the time to start my MK SD33T with 290k on the clock. Glow for an extra 30seconds or so and she starts first turn no problems. No smoke no dramas.

Can start on 4 degree mornings no probs.

Cheers!

[V8Patrol]

my MK SD33T with 290k on the clock

Its just run in then



My non turbo SD33 just clocked over the magic 500K milestone

Last trip she did to the snow area we had to double glow her..... then we had to tow start another five 4x4's that had flattened their batteries trying to get started


Must admit.... last few cold mornings here she's needs an extra glow to fire up

[RMP&O]

worked on the truck nearly the entire day today. I am making some progress and I found at least 1 major problem.

Got some more things to check tomorrow like compression.

Plan on working on it a bit tomorrow and also taking it out wheeling! Will report what I finally figure out after that.

[V8Patrol]

YOU JINXED ME

old yella refused to start yesterday








Its ok tho...... turned out to be a battery thats down on grunt
( still holding 12volts but no kick when the power was needed )

Might pay to get ya batteries "load tested"


Kingy

[hollywood]

hey rmp&o does it start when its cold and not when its just warm not sure if this can help but my mtae just had a new engine fitted in his new patrol after 17.000 ks he chiped it up and it melted no 4 piston but appart from that it wouldnt start when it was warm, but start perfect in the morning comes down to a senser thats connects to the glow plugs and the water jacket ( water temp )they are very sensetive he unpluged it and bang off it went but dont let it warmup to much it wont turn off til the engine is running, and u can burn it out, hense new senser required good luck steve.

[RMP&O]

Ok so over the last few weeks driving and messing with the Pootroll I discovered a few things. and have a few new questions!

So just to make this clear I had put new 24v glow plugs in the truck about a year ago. Used them lots to start the truck and they worked fine. Same batteries in truck now as last summer, red top optimas but recently some new wiring has been done. Nothing manjor just moved the batts to the bed behind rear seat. Grounded them to the chassis with a bolt welded onto frame rail. Seems to be pretty good ground. Ran new wire from batts to fuse box which has big ass fuses in it. Power goes to the starter from here and then to the rest of the electrical system. All just real basic shit. I didn't do this work though....

Now I blew the 24v plugs that had been in the truck nearly a year, said that above I think. I got the new ones, put them in and never glowed them more than 20 seconds at a time. I think I put power to them (glowed em') no more than 20 times ever. So I was sure they were fine. Well I decided to pull one and check it, burned up! Pull another, same thing...all 6 were wasted! So I was putting 23.6-23.9v to the plugs when I would glow them. It says on the plug 23v. So did the extra 1/2-1v burn them up!? I asked when I bought them what glow time is and couldn't get the info. Maybe these plugs are super fast heaters, ie 5-10sec plugs? Meaning if I glowed them 20seconds that burned them up? That seems more likely to me that 1v over blowing them.

Next question...is there some sort of voltage limiter on the stock glow plug system? Meaning a 23v plug only gets say 21v controlled by a limiter or regulator? Don't see anything like this in the manuals, thought maybe the auto glow plug timer or something may do it?

So I am like wtf, blown plugs, no heat, she won't start. I get out an old set of 12v plugs the previous owner had in the truck. These are NGK's and say 10.5v on them. I put these in the truck and run power to them from the 24v-12v converter. I have 13.8v at the plugs now. Concerned I might blow these with that much power I don't glow them long. These are tough plugs though and don't burn up easy. I know I have put power to them a long time in the past and they are still good. Any ways, get the truck to start for the first time in 2 months without starting fluid! I simply glowed the plugs enough and it fired right up!

So problem there solved. But still do not know what would burn up the 24v plugs? They never even started the truck once, that is how fast they went. I may have only been putting 12v to the first set of 24v plugs before. I don't recall exactly but before the batts were moved power to plugs was being pulled off only one battery, this being the opposite one from the starter battery. I do recall checking voltage a few years back and it was 12v or there abouts to the plugs. So maybe when the truck got rewired it was then putting more voltage to the plugs then before, hence why they blew up...?

Next problem, My alternator is going out. It is only putting out 20-21v and I know it is going to die completely soon! But what I am wondering is if the alt is putting out low power and say the controller on the injection pump isn't getting the right voltage...well, could that make the controller go crazy!? Recently the controller would move to stop for no reason when driving the truck and truck would die. Easy to fix, unhook the controller from the governor. But would incorrect voltage to the unit cause it to have a mind of it's own? Same with the not moving to start position, would low voltage to it cause this? And what should voltage to the unit be? When the truck was charging right before volts were around 28v coming from alt and at batteries when running. Is that correct? Just trying to determine what correct opperating voltage should be from the alt and figure out what would cause the controller to go crazy.

I didn't check compression yet because I seem to have figured out the problem. Glow plugs.

sorry for long post, just trying to paint a clear picture here and get some solid replies!

[pegasus]

Hey mate,

Sounds like you may have it finally figured out! Hope it fix's it for good.

Did you take it wheeling in the end though?????

Stew