Glow Plugs Heat Time

[s2mikon]

No. Glow plugs are a heating element that the injectors spray on to aid cold start. Then there manifold heaters that heat the incoming air in the manifold. Then there block heaters that heat the coolant in the block to aid cold starts. There also crankcase heaters to preheat the engine oil to make the engine oil flow better when cold. In arctic conditions you use all of them.

 

[DJTM]

No. Glow plugs are a heating element that the injectors spray on to aid cold start. Then there manifold heaters that heat the incoming air in the manifold. Then there block heaters that heat the coolant in the block to aid cold starts. There also crankcase heaters to preheat the engine oil to make the engine oil flow better when cold. In arctic conditions you use all of them.

Oh wow, didn't realize there were so many heaters!! Thanks for explaining that s2mikon.

 

[s2mikon]

I should have stated that not all engines have all of them, but it is something to look for when acquiring a used rig. Ether is a no go with glow plugs and manifold heaters for obvious reasons.

 

[nikitis]

You can use Ether with glow plugs, but typically if you have to, it usually means something is wrong and you should fix it, unless it's extremely cold.

I had glow plug issues, they were burnt out and wouldn't work anymore. My bus only needed the slightest spray of Ether, and I mean like 1/2 second tap of that can. A quick "tssh", and she's start up just fine. I had the glow plugs fixed on mine now and it doesn't need ether at all except on the coldest days here.

You should give your glow plugs a second chance to start the vehicle though before jumping straight to ether. Turn key to on, wait 10 seconds for the glow plugs to heat up. Then Crank, If after 5 seconds nothing, stop, wait another 20-30 seconds, then crank a second time. sometimes Glow plugs weren't hot enough at first crank. If after the second attempt fails then give a quick "tssh" of ether.

If you have a block heater, it takes about 4 hours to give the block optimal conditions, (I got this info from Ford websites from people who've done the science on it, and I tested it out this winter on my rig with a block heater and it was consistent with their findings.) but you can usually start it much easier after 1 hour of block heating, but in some temps it still will be hard after only 1 hour. 4 hours should bring you to similar conditions to summer weather cranking speeds and should crank up easily in winter. If it still does not then something else is wrong.

 

[DJTM]

You can use Ether with glow plugs, but typically if you have to, it usually means something is wrong and you should fix it, unless it's extremely cold.

I had glow plug issues, they were burnt out and wouldn't work anymore. My bus only needed the slightest spray of Ether, and I mean like 1/2 second tap of that can. A quick "tssh", and she's start up just fine. I had the glow plugs fixed on mine now and it doesn't need ether at all except on the coldest days here.

You should give your glow plugs a second chance to start the vehicle though before jumping straight to ether. Turn key to on, wait 10 seconds for the glow plugs to heat up. Then Crank, If after 5 seconds nothing, stop, wait another 20-30 seconds, then crank a second time. sometimes Glow plugs weren't hot enough at first crank. If after the second attempt fails then give a quick "tssh" of ether.

If you have a block heater, it takes about 4 hours to give the block optimal conditions, (I got this info from Ford websites from people who've done the science on it, and I tested it out this winter on my rig with a block heater and it was consistent with their findings.) but you can usually start it much easier after 1 hour of block heating, but in some temps it still will be hard after only 1 hour. 4 hours should bring you to similar conditions to summer weather cranking speeds and should crank up easily in winter. If it still does not then something else is wrong.

Ok cool, thanks Nikitis. Yeah it never got below zero so 1 hour was usually all i needed. But, if I'm ever someplace super cold I'll keep in mind the longer block heater times.

 

[BamaBus]

I have not seen where it is advised to use ether with glow plugs, except here. I guess if you are able to disable the glow plugs then you could use ether. The 6.5 the OP has, typically have the glow plugs automatically engaged at key-on unless bypassed, as it in his case.

EDIT: you will read in post #28 that even this should not be done.

 

[nikitis]

I dunno, I just know I used ether when I bought the bus and never had issues when I had hard start issues. Of course my glow plugs were mostly not working but also supposed to turn on on key on. Once I replaced my plugs, I never needed ether again so it doesn't appear to have done any engine damage.

I also don't spray tons of it either though. It really only takes a sip of ether to give it the kick it needs. If you hold the spray can for 1 second or longer you've already done too much. Just needs a quick "tssh" 1/2 second click on that air filter. Ether is very potent and your engine will suck it up no problem. Too much ether can cause damage to the engine. I never sprayed enough in it to cause damage.

 

[s2mikon]

This is why you should never use ether with glow plug preheating. The ether vapors will self ignite just from the red hot glow plug tips, the heat of compression is not needed. Due to the fact that the intake valve is open as it draws air and ether into the cylinder the red hot glow plug is exposed to the ether and air mixture and it will auto ignite in the intake air track. When this happens it can cause flash burns to the poor dope spraying the ether, start a fire in the engine compartment, blow up the air cleaner or blow the intake manifold off the cylinder head. I have seen it. It is real.



Now what does it do the the engine itself? It depends upon a lot of factors. First lets take the Detroit Diesel 2 cycle engines used in some buses. They were low compression 17:1 on many, and had steel pistons. They were hard to start when cold and ether was used a lot to start them. They made cold start kits for them that used ether from a canister and controlled with a solenoid. I used to install them. They were powered from the starter solenoid and an additional button in the cab. It had to be turning before you could inject ether. I never witnessed any problems from them. Those kits were also installed on Cummins, Mack, John Deere, Cat and many other large industrial engines. But the engines we were/are discussing in this thread are small high speed high compression 21:1 engines like the 5.7, 6.2, 6.5 GM 6.9, 7.3 IHC and any other engine in this class. What can and does happen at times is even if the glow plugs are disabled the ether air mixture can pre detonate long before the piston reaches TDC. This can cause the engine to violently kick backwards while starting and cause big problems. I have seen starters ripped of the block, flex plates broken, ring lands on the top compression ring broken and pre-chambers dislodged from the head. VW diesel engines would bend the rods just enough to lower the compression so they would not start with out ether. When you measured the piston height they would be low on a few cylinders. Peugeot would blow the head gasket or dislodge the pre-chambers. I’v seen that with the IHC’s too.



So if you want to use ether it is up to you it’s your money. But before you do RTFM first. If they tell you don’t, there is a good reason why, they have already seen the damage before you.

Sorry for the long post, but I would like to save you some trouble.

 

[nikitis]

I wonder though how many people oversprayed ether into the intake though when those calamities happen.

I and many thousands of others have done it a lot and never had issues. They wouldn't sell it in auto stores either for that exact purpose if it wasn't useful. They even literally label it starter fluid. No body has been sued for using it. I just suggest don't overspray it if you do. one quick Tssh each crank. If it begins to start but fails then I'd look into fuel because you have spark since it ignited when trying to start but didn't have fuel getting to it to keep it going so it failed due to fuel. You should never need to keep spraying ether to keep the engine running either, if fuel is getting to it it should start with a quick "tssh", then the fuel take over. If you feel like you have to keep using it to get it rolling, then you could damage your engine, in that case I would recommend not doing it.

 

[TheHubbardBus]

I and many thousands of others have done it a lot and never had issues. They wouldn't sell it in auto stores either for that exact purpose if it wasn't useful. They even literally label it starter fluid. No body has been sued for using it.

Do you realize you're arguing with people in this thread that have literally spent decades of their lives working on/with diesels in a professional capacity? But what do they know, right? I hope casual readers here who don't know who's-who can separate the wheat from the chafe.

 

[Thurmond1317]

Welllll lucky me, looks like I'll be getting and installing some new glow plugs

Turns out while my switch was a massive part of the problem, it wasn't the whole part. I bought some from diesellogic to be able to start it and move it to my shop. I'm excited to introduce it to my welder lol. But once it's at the shop and by all my tools, I'll be able to fully inspect the ignition system and maybe put a glow plug controller. I'd love to not have to worry about accidentally flipping my glow plug switch.