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300 TDT hard to start with ultra low sulfer diesel

I have a 1982 300TDT (station wagon).

I have been having a hard time getting it to start in even slightly cool weather since our fuel dealers here in California were forced by regulation to switch to ultra low sulfur diesel. Everyone says that has nothing to do with my car not starting, but I have been going through all the other possiblities with little success. I first noticed the problem last summer after parking the car overnight in the High Sierra at about 7,000 feet. In the morning I had to crank the motor for a long time, like it was 15 F, but it was only about 40 F. Now that it is winter and the morning temps are in the 20s F I can sometimes get the car to start if I had a block heater on all night, but today it would not start at all. The new fuel tends to flood the engine and then I need a tow to about 50 mph and drop it in low to get it to start.

I have replaced the filters. (but I had cracked a line and made sure that there were bursts of fuel when I turned the motor over.) I have also replaced the glow plugs. I just ordered a new glow plug relay from Bosch that keeps the glow plugs energized for three minutes after the engine starts. Maybe that will help.

I use 2 oz of automatic transmission fluid and 3 oz of Power Service brand diesel additive for lubricity, centane boost and anti gelling per

10 gallons of fuel.

I also bought a new Sears DieHard International battery, but I still have trouble getting the motor to start with the new fuel. I bought a tank of low sulfur, the old stuff, on the Navajo reservation last month and the next morning my TDT started fine even with frost on the windows and the grass. That afternoon I filled up with ultra low sulfur diesel in Moab and the next morning it was 42 and I could not get my car to start. I had to have someone come from a serivice station and give me a jump start and run a hair dryer under the hood for two hours warming up the injection pump and lines.

I live in Easten California, and our fuel all comes from the L.A. basin and is mixed for their conditions.

My motor has been well cared for, but is getting tired with 394,000 miles on it. But the starting problem got worse precipitously when the ultra low sulfer diesel came along.

I hope to do an overhaul later this winter, but I would really like to be able to get the car started for now as it runs great when it is going. It has excellent power and does not smoke excessively.

Does anyone have any other ideas to try for corecting hard starting?

Thanks.

Paul Fretheim snipped-for-privacy@inyopro.com

Reply to
heav
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Reply to
robrjt

Glow it three times before cranking the engine.

Adjust the valves.

Reply to
T.G. Lambach

At one point my car was WAY off in terms of valve adjustment. But the glow plugs have always been good and even in very cold weather it's been my experience that with good plugs and bad valve timing the car will start.

But, with perfect valve timing and bad plugs starting is going to be, um, "an issue".

Ideally of course you'd renew the glow plugs, adjust the valves, run some diesle purge through it and rebuild the injector tips.

But of all those things glow plugs have the most significant impact on starting by a LARGE margin.

Reply to
Richard Sexton

Thanks for the advice.

I will try some water purge additive, but I am pretty sure the fuel is coming through pure as I have changed filters and cracked a line and inspected the fuel and it looked and smelled normal.

I should have mentioned that I always adjust my valves at 15,000 mile intervals. They were last adjusted at 384,000 and now the car has

394,000, so they were adjusted 10,000 miles back.

heav wrote:

Reply to
heav

I should also mention that I installed rebuilt Bosch injectors at

377,000 miles. I noticed a big increase in power and smoothness of operation, but also increased blow by when the engine started firing at the correct moment. The motor also began to run slightly cooler, back how it did when it was 200,000 miles newer. The tired springs in the old injectors apparently caused the injectors to fire too soon.

The increased blow by tells me it is time for liners and pistons and valves and seats, even though the engine runs like new as far as power and smoothness is concerned.

I should have the new relay > I have a 1982 300TDT (station wagon).

Reply to
heav

I installed a new relay into my car... 95 E300D... and now sometime the glow light doesn't even come on... What else can be changed?

Reply to
Tiger

Where did you get the relay that keeps the plugs hot for 3 minutes?

Reply to
szcz

I ordered mine from autopartswarehouse.com

Paul

Reply to
heav

I had the same problem starting problems but was with a VW turbo diesel. Have used toulene (1/2 liter) in the gas tank and did the trick for me. Toulene can be bought at any hardware store in the paint department. It helps increase the combustability of the diesel in cold weather. You might also want to try automatic transmission fluid(1/2 liter) in the gas tank to help clean and lubricate the injectors every 6 months. Some might not agree with what i have done, but it worked for me. My

91 Jetta had over 375000 kms on the original factory engine

"heav" wrote

Reply to
HANK

I spent about $350 US on the glow plug system without much improvement in starting, and then discovered that when the car sat overnight, the fuel was draining out of the in-line filter on the primer pump. This turned out to be because the short section of fuel line (3.6 cm) that connects the in-line filter to the pump had deteriorated and was not sealing properly.

I replaced this bit of hose and now the car starts. It still has compression issues (394,000 miles on it), so the starting is difficult when cold and I have to use a block heater, but at least it gets going now with about two minutes of cranking when it is below freezing.

Thanks to everyone who offered ideas.

I do think it runs smoother after starting with the new Bosch relay that keeps the glow plugs on for three minutes after the car starts.

Paul

heav wrote:

Reply to
heav

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