Hi diesel experts
I'm debating myself on how to fix my tired 3B engine.
So this may become a longer therad: From diagnosis, over planning to chasing parts and eventual rebuild or fix.
The backstory:
I own a 1985 BJ73, with a 3B (iteration 1) engine for three years now. 320 000km total on the odo, 15k put on it by myself. It is the original engine to the vehicle.
Apparently the engine has never been opened: Still the original composite head gasket on it (after 2000 latest one would have used the steel gasket, I guess) and also no telltale of wrenching or impact driver marks on any bolt (including crankshaft pulley bolt). Glow plugs are new for sure and probably the injectors may have been rebuild (who knows).
The engine actually runs fine: Starts on first rev, doesn't consume any oil, no suspicious smoke, no rough idle, accepts throttle well, no leaks, no fume or oil in coolant.
Cooling works fine: As the original gauge is not accurat, I installed a motometer gauge. Since I run it with the original sensor, the gauge is not calibrated for, the reading isn't an exact figure. But the gauge is very sensitive, so I can see slightest changes in the temperature. No signs of overheating by any means. When warmed up, the temp sits at constant levels, even at 90-100km/h (56-62 mph) on the Autobahn. 5° increase on inclines, nicely coming down when going level again.
Oil pressure builds up a bit slow on first start: On nearly idle, EDIC may shut it down before pressure comes up, so, despite it starts fine with little throttle, one would need to wind the throttle up in order to help with oil pressure. When it had run and is warm, oil pressure is no issue at all.
** BUT it has significant blowby: ** The oil cap dances rock 'n roll on the oil filling opening and the crankcase ventilation pipe emits so much exhaust gas, one can clearly see it and smell it in the cab. Also the engine is tiered. The 3B certainly is not a rocket in the BJ73, but some horses must have left the stable.
It wasn't great already when I got the truck, but it slowly worsens.
I'm now at the point I do not trust the engine any more, and I do not dare asking anything high power from, it as I fear to overstrain it. Going inclines or offroad always comes with concerns.
So, I 'm debating to have it rebuild. I want it trusty and (to the possible extent of an old 3B) powerful again.
(Yes, I know: I should consider an engine swap. But engine swaps come with legal and tax implications in Germany. I also see no suitable, reliable engine, that would be plug&play, anywhere available here. I unlikely can afford both, a different engine plus a rebuild on thatone. Any fancy conversion is out of the question for me, too. The engine is original to the vehicle, which I honor and value.)
But how to approach this situation on such an old 3B?
QUESTION:
Considering the symptoms: Is a full rebuild actually likely to be necessary? Should I go for compression test and 'drop of oil in cylinder' first, hoping I get away with finding & fixing a valve issue only? Or do 320 000km make the piston rings likely to be the culprit? Or do 320 000 km in general call for a rebuild of block and pistons?
Certainly a full rebuild would be favorable, particularly considering the availability of parts, which is rapidly decreasing for the 3B.
But eventually it is a question of budget for work and parts.
I neither have the abilities nor the tools nor room to do a rebuild myself. So I would need to leave any rebuild with an expert shop.
QUESTION:
What parts would typically need to be replaced (considering nothings is damaged, just worn)? (I don't want to replace everything that could be replaced; just the wearing parts).
Does anybody have a parts list for this purpose for a 3B (iteration 1 1984-1988)? (I'm always concerned about having all small parts covered, like wahers, gaskets, single-use parts ..)
What would be the best strategy to source parts, in order to keep the time for the rebuild down?
I can certainly make a plan with the expert on what to replace, setup a parts list (with help of you guys here) and get them sourced before the endeavor starts.
But QUESTION: How to deal with those parts that come in classes and must match (e.g. 1 2 3 or 1.0, 0.75...) or are even subject to measure the wear (like e.g. piston, rings, sleeves). I guess I have to open the engine first to see or probably measure what is needed? Which would mean I have to plan for two or more weeks pause to get the parts in?
Any advice is highly appreciated.
Thanks Ralf
I'm debating myself on how to fix my tired 3B engine.
So this may become a longer therad: From diagnosis, over planning to chasing parts and eventual rebuild or fix.
The backstory:
I own a 1985 BJ73, with a 3B (iteration 1) engine for three years now. 320 000km total on the odo, 15k put on it by myself. It is the original engine to the vehicle.
Apparently the engine has never been opened: Still the original composite head gasket on it (after 2000 latest one would have used the steel gasket, I guess) and also no telltale of wrenching or impact driver marks on any bolt (including crankshaft pulley bolt). Glow plugs are new for sure and probably the injectors may have been rebuild (who knows).
The engine actually runs fine: Starts on first rev, doesn't consume any oil, no suspicious smoke, no rough idle, accepts throttle well, no leaks, no fume or oil in coolant.
Cooling works fine: As the original gauge is not accurat, I installed a motometer gauge. Since I run it with the original sensor, the gauge is not calibrated for, the reading isn't an exact figure. But the gauge is very sensitive, so I can see slightest changes in the temperature. No signs of overheating by any means. When warmed up, the temp sits at constant levels, even at 90-100km/h (56-62 mph) on the Autobahn. 5° increase on inclines, nicely coming down when going level again.
Oil pressure builds up a bit slow on first start: On nearly idle, EDIC may shut it down before pressure comes up, so, despite it starts fine with little throttle, one would need to wind the throttle up in order to help with oil pressure. When it had run and is warm, oil pressure is no issue at all.
** BUT it has significant blowby: ** The oil cap dances rock 'n roll on the oil filling opening and the crankcase ventilation pipe emits so much exhaust gas, one can clearly see it and smell it in the cab. Also the engine is tiered. The 3B certainly is not a rocket in the BJ73, but some horses must have left the stable.
It wasn't great already when I got the truck, but it slowly worsens.
I'm now at the point I do not trust the engine any more, and I do not dare asking anything high power from, it as I fear to overstrain it. Going inclines or offroad always comes with concerns.
So, I 'm debating to have it rebuild. I want it trusty and (to the possible extent of an old 3B) powerful again.
(Yes, I know: I should consider an engine swap. But engine swaps come with legal and tax implications in Germany. I also see no suitable, reliable engine, that would be plug&play, anywhere available here. I unlikely can afford both, a different engine plus a rebuild on thatone. Any fancy conversion is out of the question for me, too. The engine is original to the vehicle, which I honor and value.)
But how to approach this situation on such an old 3B?
QUESTION:
Considering the symptoms: Is a full rebuild actually likely to be necessary? Should I go for compression test and 'drop of oil in cylinder' first, hoping I get away with finding & fixing a valve issue only? Or do 320 000km make the piston rings likely to be the culprit? Or do 320 000 km in general call for a rebuild of block and pistons?
Certainly a full rebuild would be favorable, particularly considering the availability of parts, which is rapidly decreasing for the 3B.
But eventually it is a question of budget for work and parts.
I neither have the abilities nor the tools nor room to do a rebuild myself. So I would need to leave any rebuild with an expert shop.
QUESTION:
What parts would typically need to be replaced (considering nothings is damaged, just worn)? (I don't want to replace everything that could be replaced; just the wearing parts).
Does anybody have a parts list for this purpose for a 3B (iteration 1 1984-1988)? (I'm always concerned about having all small parts covered, like wahers, gaskets, single-use parts ..)
What would be the best strategy to source parts, in order to keep the time for the rebuild down?
I can certainly make a plan with the expert on what to replace, setup a parts list (with help of you guys here) and get them sourced before the endeavor starts.
But QUESTION: How to deal with those parts that come in classes and must match (e.g. 1 2 3 or 1.0, 0.75...) or are even subject to measure the wear (like e.g. piston, rings, sleeves). I guess I have to open the engine first to see or probably measure what is needed? Which would mean I have to plan for two or more weeks pause to get the parts in?
Any advice is highly appreciated.
Thanks Ralf
I was looking for, which I will follow. Thank you. Highly appreciated.
and decided to take action.
