bj70 new head installed, questions (1 Viewer)

[tytuk]

howdy all, i have a 1985 bj70 12v, bought with a bad head, had a new one installed. drove alright for about 300km then would not start one day was real cold and not plugged. plugged in gave it a jump still no start. so now it has sat for 2 months, its been very cold went out today and plugged in for 5 hours gave it a jump still no start. when i was messin with it i notice the upper radiator hose was under pressure so i opened radiator cap and antifreeze overflowed. should i be worried of a bad head and gasket install or could it be air bubbles from recent radiator flush and refill or ... thanks

 

[PhrogsPhorever]

Did you do the work, of did you have it done?

Could be air bubbles in the cooland lines, which could be a whole other pile of ass-pain if the coolant system wasn't "burped" and coolant wasn't flowing parts of the engine for the 300Kms you drove it. Upside down installed thermostat?

You see any oil in the coolant? You see any coolant in the oil?

If you had the work done by a shop, drag that thing back to the shop and tell them it no workie and what you saw. Make them stand behind their work.

If you did the work, pull the head and look for signs of HG failure.

Aside from that, check your fuel system, filters, EDIC, lines, etc.

 

[tytuk]

thanks, called them(shop that did the work) yesterday,said they come up and pick up the truck next week. no oil or coolant mix form what i see, but it wasnt mixing when the head was bad the first time, just gases present. so pretty much there is no reason that the radiator would be under presure after all that time unless something is quite wrong? how fu#$ am if i drove it over a moutian pass with air bubbles in radiator? needle never indicated anything getting hot. Also does a 1985 canadian bj70 have a high altitude adjustment/compensator? thanks for any info!

 

[Radd Cruisers]

HAC was probably not on your BJ70.

Pressurized cooling system might be from poorly seated head gasket - then again, might not be. It is possible for pressure to be in there and no head problem to exist. The surfaces need to be really clean and dry, and prepared to the right smoothness (need to be a little rough, not polished) when the gasket is put into place.

Even with a bad gasket, cracked head etc... a 3B will run if there's fuel, glow (or enough heat), and a starter that's cranking it over decently. I've seen these engines start and run with water pouring out the exhaust from a cracked head, water fountaining out of the rad etc.

Check to make sure that you have fuel getting to the injectors - crack a line near the injector and crank it over - if you get little spurts of fuel coming out, then you probably have fuel.

The fuel control rod can be removed (from EDIC motor to inj pump) and the Injection pump will default into the run position.

Pull your glow plugs and glow test them with a battery or decent sized battery charger (10A will do it nicely). It is very common for the wrong ones to be installed or for them to be burned out. Don't fool yourself into thinking a resistance test is good enough - glow them and see how long they take to get a good red/orange colour near the tip.


~John

 

[tytuk]

thanks! without a HAC is there any way to tune it for high altitude? i live @ 10,000+ feet and she runs ruff with a high idle (injector pump diaphragm maybe???) and lots of black smoke. the injectors were rebuilt less the a year ago.
as far as the head being prepared i did have to get it machined slightly to get the pre-combustion chambers to sit with in spec, and it was kinda on the polish side. any ideas if it is a poorly set gasket how to prepare the head for another try?