Wintertime hard starting

[BlueDog]

My '89 Jetta with 1.6NA starts great 8 months of the year. Hit the key, I think one revolution of the engine and it's running. Does not like to start in the winter. Pulled the injectors to view the glow plugs. They all glow cherry red. Checked the compression. Three were about 475 and one was 430. Crank it for about 20 seconds and it eventually starts. Any ideas for improving this?

[BlueDog]

What about a thinner oil like 5W30 instead of my current 15W40? Would this allow it to spin faster when cold? Maybe start more readily?

[TylerDurden]

Absolutely. I use synthetic 5-40 diesel rated.

[BlueDog]

I have some concern about synthetic oil making for oil leaks. Maybe I'll try a 10w-30 diesel rated oil.

[greg lousy]

I would look into IP timing then maybe injector nozzles... should be starting real good with working glow plugs and your good compression

[colby]

Do you have the cold start lever out when starting in the cold months where it doesn't start good? Or is it in, or do you ever even use it? Some were finicky and needed it out to start cold, most I've found start better with it in, and when its running, pull it out. Are you applying some accelerator pedal when cranking? That usually helps Your compression numbers are good, and if all the glow plugs are firing red hot, it should start without issue.

Cranking speed is really a big killer on these. You may be able to stuff a group 65 battery in there. We put one in my father's TDI, and I believe an 84 Jetta as well.. those suckers have like 800+ cold cranking amps and will really spin them over quick. The 15w40 diesel oil is pretty thick when its cold, I've run synthetic in the older engines without issue and never had any oil leak problems other than the valve cover gaskets but I haven't owned one yet that the valve cover didn't leak on.. the 3 main oil seals on the front of the engine (camshaft, intermediate shaft + o-ring, and crankshaft) can all be changed relatively easily.

Having said all this, I ran 15w40 year round in my 91 and the only time it wouldn't start is when the glow plugs were burned out. Had to use lighter fluid to get it to light off one day...

[BlueDog]

I'll try leaving the cold start knob in when cranking and pull it out when it starts. I have found that pressing the accelerator while cranking helps it start a little sooner. But, I wonder if I have another problem at the same time. I can be driving along doing fine but when I slow to a stop for a stop signal the engine chugs, vibrates and slowing dies out; like it's out of fuel. Crank the starter and in about 3 seconds it starts back up and away I go. Acts to me like it runs out of fuel. So I changed the fuel filter. I thought that fixed it but a couple days later it started doing it again.

[supersisu]

Got my 1.6 truck started a few days ago by hitting the glow plugs with a propane torch. It took awhile to get the area warm and you have to be a bit careful not to melt anything and keep a smothering rag handy.

I think my winter cold start problems are: 1) Heat from glow plugs immediately absorbed by cold cylinder head, 2) Engine turns over slowly due to cold oil. 3) Cold battery

I take my battery indoors in really cold weather, and I would love to plug in the engine block heater but I usually park on city streets.

[BlueDog]

All is well now. I was getting air in the fuel line. That made it crank for a long time until it got a good amount of fuel. Fixed the air leak.
I also put in 5w-30 oil. Spins faster now; starts good.

[surfcam]

From what I've read. 5w-30 is only good in the cold winter. Not suppose to be good when things warm-up. People north of the 60 parallel use it alot. I like 0w-40, 5w-40, and 15-40. I'm right on the 49th parallel. I believe this is in the Bentley.