EC15B heavy start

[Mattir]

Hi again,

the -15B is in sleep mode for the winter, but one thing initiated this question.

Being unused for 3weeks, I tried to start the engine. Key in and wait for a cpl sec., glow plug light off and turn. Low starter rpm, did not start. Another start effort now with a little bit more revs, but still not starting. 3rd effort and finally started.

The main question is that what causes heavy start. Temp outside was typical Finnish +4C and that should not be an issue. The glow plugs have right resistance and are working ok. The battery is small but seems to put some 200+A out against a short circuit wire with a clamp ammeter. The ammeter has max. 200A and thus cant tell the top readings.

Changed the hydraulic oil to -46 grade in summer and have started the engine multiple times. That should not affect starting.

Also replaced a hydraulic hose serving the bucket tilt ram, hose being between the boom and dipper

The only suspect is the starter, Bendix-unit and the wiring to the starter and engine ground terminal.

Need to start the engine only after the winter so we have a plenty of time to quess what the cause might be.

[Muz]

The glow plug timer relay could also be faulty, shutting off too early to allow the glow plugs to heat up properly. TBH the batteries are too small they lose cranking power too easily when the temperature drops

[Mattir]

The glow plug timer relay could also be faulty, shutting off too early to allow the glow plugs to heat up properly. TBH the batteries are too small they lose cranking power too easily when the temperature drops

Yes, the glow plug relay allow only maybe 2..3 sec. heating and cuts off. Therefore I heat it up a cpl of times before trying to actually start. Will check where to get the g p r affordably. Tnx Muz

[Mattir]

Yes, the glow plug relay allow only maybe 2..3 sec. heating and cuts off. Therefore I heat it up a cpl of times before trying to actually start. Will check where to get the g p r affordably. Tnx Muz

replying to myself.

the relay is set to have a 6 to 7,4 sec heating time. My 3 sec is out of spec. The relay most likely has some moisture/ water in it

https://www.manualslib.com/manual/11....html?page=141

[Muz]

replying to myself.

the relay is set to have a 6 to 7,4 sec heating time. My 3 sec is out of spec. The relay most likely has some moisture/ water in it

https://www.manualslib.com/manual/11....html?page=141

Yeah lost count of the number of EC15's I have to 're glow' before starting beginning to wonder why I ever liked these

[Muz]

My 3 sec is out of spec. The relay most likely fooked

FTFY

[Mattir]

4B7389BF-B87C-4088-A201-DC3D2DE4BD6A.jpgBB025B41-AD7B-4EE0-B875-29C95611662E.jpg

Here it is. The screwdriver is pointing at the NGK glow timer circuit. The circuit diagram is available in the internet as well in case anyone wants to practise soldering and electronics troubleshooting. Measured all of the components and major differences were only in electrolytic capacitors. They tend to loose their capacity over the years.

New complete timer is available at around 70...90€, so I will spend some time with this one and change the capacitors as I have a good supply of those.

the other relay in the pic is the power relay that actually feeds the power to the glow plugs.

The delay timer is behind the relay frame so one needs to dismantle the metal chassis. Only one bolt with 12mm socket need to be opened.

[Muz]

[ATTACH=CONFIG]3992[/ATTACH][ATTACH=CONFIG]3993[/ATTACH]

Here it is. The screwdriver is pointing at the NGK glow timer circuit. The circuit diagram is available in the internet as well in case anyone wants to practise soldering and electronics troubleshooting. Measured all of the components and major differences were only in electrolytic capacitors. They tend to loose their capacity over the years.

New complete timer is available at around 70...90€, so I will spend some time with this one and change the capacitors as I have a good supply of those.

the other relay in the pic is the power relay that actually feeds the power to the glow plugs.

The delay timer is behind the relay frame so one needs to dismantle the metal chassis. Only one bolt with 12mm socket need to be opened.

Cool .. so you rekon its a fall off in capacitor performance that's the culprit ? How come an old radio still works after 40 years then for example ?

[Mattir]

Cool .. so you rekon its a fall off in capacitor performance that's the culprit ? How come an old radio still works after 40 years then for example ?

Yes, that is the verdict of my one man jury until proven otherwise. The capacitance value of a capacitor decreases and as it has less capacitance, it takes shorter time to charge thus resulting in a shorter glow time.

Electrolytic capacitors dry out over the years as they have liquid inside. The old radios have those as well but the age old radios (being as old as we are) have paper or mica insulated capacitors moulded in bitumen or parafin. Additionally there are ceramic caps. They last forever unless overheated.

Will test my theory and replace the caps. when the right moment comes.

[Muz]

Yes, that is the verdict of my one man jury until proven otherwise. The capacitance value of a capacitor decreases and as it has less capacitance, it takes shorter time to charge thus resulting in a shorter glow time.

Electrolytic capacitors dry out over the years as they have liquid inside. The old radios have those as well but the age old radios (being as old as we are) have paper or mica insulated capacitors moulded in bitumen or parafin. Additionally there are ceramic caps. They last forever unless overheated.

Will test my theory and replace the caps. when the right moment comes.

I'm interested in your theory because I was trying to get an old ZX Spectrum going again a year ago only to come up against the same problem, in the end I binned mine and bought a replacement on Ebay for not a lot, to relive the days of my youth .. but the guy had replaced all the caps to make the thing work

[v8druid]

capacitor theory looks to be sound then guys ..... often wondered about the difference between electrolytics and mica/paper ones ... apart from their obvious physical size difference

[Mattir]

Repaired

79843D2D-A527-4FFC-A947-C151FAE4BF42.jpg

6 seconds!

Here it is. The old caps were replaced with ”new” ones. The new ones are my old stock from the 1990’s and since no suitable ones were available, I built that pinkgreenish cluster to get 25uF. The 0,47uF was replaced with a non electrolytic cap.

Additionally there might have been one poor solder and that was corrected as well.

saved 100€.

[Muz]

Bloody good job I think that might steal the Plant and Construction cheapest 'proper' fix prize of 2017 saving 100 Euro with a 20 pence part fix Well done Mattir .. you will have to post a '-20deg C cold start Vid' to gain your prize though

[Mattir]

Bloody good job I think that might steal the Plant and Construction cheapest 'proper' fix prize of 2017 saving 100 Euro with a 20 pence part fix Well done Mattir .. you will have to post a '-20deg C cold start Vid' to gain your prize though

Thanks.

Have taken the battery out for charging and the outside temp is only +0C with some slush on the ground so you will have to wait for the video. Btw, what is the prize something tangible or just a neverseenbefore amount of forum glory?

[Muz]

Thanks.

Have taken the battery out for charging and the outside temp is only +0C with some slush on the ground so you will have to wait for the video. Btw, what is the prize something tangible or just a neverseenbefore amount of forum glory?

Oh Yes .. you will disappear through the dry ice smokey spangly curtains as Mattir the 'Apprentice Joiner' and re emerge as Mattir the " *person of special qualities* " ....but wait ....... we have a month and a half to wait yet till the end of 2017 for someone to steal your impending crown .. I think it will be a tough job to beat that though .. plus we need the evidential material and hard evidence of the cold start .. and you know there are some hardened sceptical punters round these parts, we will need to see a temp of the block being sub zero before the job commences .. we don't do fake awards round these parts ( the committee will know if you've stuck the thermometer in a bag of ice beforehand )