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DieselScout
11-03-2014, 09:56 AM
My '82 244 has been having more difficulty starting than it used to, and with winter coming, I would like to see about diagnosing this soon.

The glow plug light stays on for about 45s (No matter the temperature) before it goes out. + The car is taking longer to start than it used to (Even in warm weather)

It got worse recently when my injector line started leaking (currently looking to replace)

Are there any other potential reasons for the longer starting time?

anders
11-03-2014, 11:28 AM
It's pretty easy to check the first four glow plugs with a test light or multi meter, five and six little more more difficult, but doable. Check those first.
How is the fuel filter? Fuel supply lines in good shape And tight?
How many miles are on it?

ngoma
11-03-2014, 08:26 PM
See the sticky on hard starting for more ideas.

DieselScout
11-04-2014, 08:41 AM
Just tested the glow plugs with a test light; all 6 look good.
The fuel filter was replaced this Summer and the valves were adjusted.

One fuel line is leaking.

Car has 194k miles.

Battery is at appx. 10v when glow plugs are on, is this OK?

Could this have anything to do with the fuel pump or injectors?

ngoma
11-04-2014, 12:33 PM
Unbolted the rear GP buss bar to check GPs #5 & 6 independently?

Battery strength? Starter? My starter had recently been going bad but gradually; it was hard to really notice the slower cranking speeds. Replaced the starter and Bang! Now it starts almost before I twist the key!

What is the battery voltage before energizing the GPs?

Injector line possibly a contributing factor-- how much is it leaking? From where?

Injection pump could also be a factor, esp. if the mainshaft seal leaks air into the IP while parked. Have a helper try to start it while you watch the transparent fuel line into the IP, watching for air bubbles.

Volvoist
11-09-2014, 04:54 AM
Yes... You MUST test each plug independently. You may need a new realy(s) and/or temperature sensor in the back of the head. Also, do not run 15w40 (or thicker) oil in these engines. I, as does VW, recommends a 5w40 synthetic. 0w40 synthetic also works well. Thicker dino oil in these engines is not ideal. You will also notice a starting improvement, less (if any) need to adjust the valves, etc.

DieselScout
11-12-2014, 08:04 AM
I didn't check 5 & 6 independently; I'll also have to check out the IP.

The battery voltage before glow plugs are energized is 12.8v.

It's leaking at the hard line just a few inches before the injector (3, I think?) I put some epoxy on it for now to slow the spray down to a leak.
It still leaks enough that after driving, when I park the car and get out, I can smell the diesel from the engine.

I run 10w-30 in the warmer weather and the 5w in the colder weather. (I think that's what the original Volvo manual recommended)

Would a bad temperature sensor be the reason why the glow plugs are on for 45s no matter the temp outside?

RedArrow
11-12-2014, 09:13 AM
It's leaking at the hard line just a few inches before the injector (3, I think?)
...
I run 10w-30 in the warmer weather and the 5w in the colder weather

Is it fully synthetic? Just being curious about it. (I use Mobile 1, a fully synthetic TURBODIESEL TRUCK 5W40 engine oil at all times. )


Would a bad temperature sensor be the reason why the glow plugs are on for 45s no matter the temp outside?

Mine did the same right after I routinely inspected rear belt&rear coolant hose, while tinkering back there I accidentally removed wire from sensor at the back of the head. It signaled glow system that engine was fully cold so they stayed on for much longer, at every start-up (same with warm engine). It`s a useful trick for starting a d24(t) that does not start when engine is hot (=has low compression). Check that wiring especially if you have contamination near your pump (D fuel eats plastic for breakfast). I do have some old crispy wires here&there also. It must be a Volvo thing. :(
Also you could connect 1st cyl temp sensor to your glow plug just to see whether the other sensor is still functioning or not.

745 TurboGreasel
11-12-2014, 07:28 PM
It's leaking at the hard line just a few inches before the injector (3, I think?) I put some epoxy on it for now to slow the spray down to a leak.
It still leaks enough that after driving, when I park the car and get out, I can smell the diesel from the engine.
2000 PSI, that epoxy has no chance, and be careful, the spray can cut straight to the bone.

They usually break because they are twisted. loosen both ends of every hard line, and retighten them to relieve any strain. Also each needs a metal rubber anti-vibe clip.

I run 10w-30 in the warmer weather and the 5w in the colder weather. (I think that's what the original Volvo manual recommended)

Would a bad temperature sensor be the reason why the glow plugs are on for 45s no matter the temp outside?The wire harness is probably more suspect than the sensor itself.

v8volvo
12-29-2014, 05:00 PM
The wire harness is probably more suspect than the sensor itself.

Or maybe connector fell off the temp sender at the back of the head (under rear cam sprocket).

Very long glow time at all times will be hard on the plugs, alternator, etc... worth tracking that down.

DieselScout
01-18-2015, 09:09 AM
Replaced my alternator, all the hard lines and checked glow plugs, which are all working and switched to 5w-30 for the January/February. Car is running much better now.

Next up is to track down the glow plug/temp sender/wire harness issue...