Loss of power and overheat problem... on the road! (1 Viewer)

Joined
Aug 21, 2015
Messages
15
Location
Toronto
ih8mud community!
This is my first post. I've been learning from this forum for half a year now.
Thank you to all the active members who posted all that helpful information!

I lived in Canada for the last 4 years and a friend of mine, also a cruiser geek has sold me his 1983 BJ60 3B with H55 transmission. I was hooked right away and spent an entire winter restoring it and dreaming about the places to go to. I fabricated a heavy duty roof rack, swing arm bumpers, etc. I think I will post a restoration documentary at some point...
About 2 month ago I left Canada to go on a road trip around the USA from Toronto, down the east coast, through a lot of national parks and up the west coast again. Most of the problem that have appeared were easily fixed due to this amazing forum!

Now, it's time to become an active member myself and maybe help out some people with similar problems through publishing this one:

About 500 miles ago I experienced a power loss. I was going on the highway (with 60 mph max speed) and all of a sudden I couldn't climb the smallest hills anymore. Shortly before that I noticed that the engine makes a more distinctive clacking noise, mostly noticeable in lower rpms. I thought that my valve clearances were off maybe, even though I adjusted them about 6000 miles ago.
At this point I should probably mention that I am not an experienced mechanic at all and most of my knowledge comes from researching things online.
Anyways, I adjusted the valve clearance (They were off) and thought that would fix the problem. For some reason the clearance had changed rapidly during 6000 miles of driving, which is a mystery to me too... Sometimes when I experience the power lossand I am not even able to get up a hill in 3rd gear the engine starts to overheat as well, once to the point that I had to stop and cool down. I only have the factory gauge though. (I know it's not very precise) I would say it's about 30% less power. My friend assumed that I have air in the system. This was true, I bled the system and injectors and found a few bubbles. That still didn't fix the problem tho...

I'm just gonna list the things done to the engine to simplify this thread a bit: (Nobody wants to read an essay ;) )

The problem:
- 30% power loss(even on flat road) Appears often, and disappears sometimes after having cooled down a bit. Then all of a sudden all the power comes back.
- overheating during power loss(especially when going up any bit of slope)
- louder clacking sound then usual
- Some black smoke when shifting down or accelerating. (I am in New Mexico right now with 8000 feet altitude. I have read that it is normal because of the air intake...)

Before I left i did this to the engine:
- I changed all the fluids, (Engine, transmission, transfer, diferentials)
- Changed oil filter and fuel filter. (Bled the system)
- Adjusted valve clearances.
- Lubricated hubs and joints on propeller shaft
- Started mixing in a bit of 2 cycle oil and injection cleanerin the tank.

What I have done to fix the problem:
- I changed the hand priming pump (Bosch) The old one was leaking and I assumed air to get in.
- Bled the system again
- Checked all the fuel lines for leaks even the one that goes into the tank. (Cut a maintenance door inside the truck to look at the fuel line) Everything was fine. The bottom got oilsprayed, most of it is pretty messy but very well preserved.
- Changed the air filter
- Checked propeller shaft and other parts for loose connections and play. (Propeller shaft was loose but the noise was the same after tightening it)
- checked coolant. (It looks green yellow ish and is a bit foggy but it doesn't look oily or so.
- checked water hoses, everything seems to be fine, Theradiatordoesn't leak either.

What I plan on doing next:
I bought seafoam to clean the engine. (Fill up the fuel filterwith it) Since the amount of miles on the engine (possible without any conditioners etc) is unknown, (odometer broke at 336.000km) there could be a lot of dirt that might have seized up an injector. I have read that a seized connector could cause a clacking noise as well. An of course a power loss...

- Should I try to mess around with the fuel setting on theinjection pump?
- I just found out that my fan is loose on the shaft, which would mean that it slips on the shaft when it has to work hard/has more resistance. I felt the nut but i could feel some pins (probably a lock nut I assume). What's the best way to tighten that? I doubt it has anything to do with thepower losstho (correct me if I am wrong)
- I also just saw one of the hoses with the banjo connection, going to the fuel filterhas quite a few cracks. Can it be that it's sucking air through them? I think it would leak diesel if they would have a hole somewhere... or maybe not? (I guess I should replace it anyways...)

I apologize for this essay like thread, I really hope to fix this problem since I am going to drive through the hot canyon lands soon... Please let me know if anything needs clarification, or if you need any more information to help me solve this problem. I very much appreciate all of your help! Thanks in advance!

Marco
 
Joined
Aug 21, 2015
Messages
15
Location
Toronto
I found out that the fluid coupling is a bit loose on the shaft, but that shouldn't cause those problems. The little screen filter in the side of the lift pump is clean too.
I filled up the fuel filter with seamfoam twice and it kind of seems to be running a bit better, but still not back to normal.
I'm running out of ideas....
 
Joined
Jun 13, 2005
Messages
3,513
Location
Centre of the universe
Hmm I dont think the overheating appears when your truck looses power, but rather the truck looses power when it overheats. That clacking you hear is called nailing and will kill your engine if you leave it. It comes from too advanced timing. As the truck overheats the fuel begins to ignite as well as burn faster. It also has the net effect of killing power as you fuel is essentially working against a piston under compression stroke and sheds enormous amounts of heat into the engine, exaggerating your heat problem. The lower the rpm the more time the fuel has to burn and the piston is slower so the engine becomes even more over advanced.

If I were you Id:
adjust pump timing to be slightly retarded. Quick and dirty method is to move the pump stamp line just slightly lower than the engine line.

wire the fan so that it doesn't slip

Look for gaps to where the radiator mates to the fan shroud and use weatherstripping to seal it up, or bits of rag will do in a pinch. Those gaps sabotage incomming cool air and replace it with hot engine air

If heat is still an issue perhaps yank the thermostat.

Ill see if I can get some pics for you regarding your pump timing.
Feel free to give me a gingle if you need a walk through on the phone as you can't drive it like this. You will break the crank or blow a head gasket or burn out your rod bearings... the list is long on what damage you can do

7785496460
Greg
 
Last edited:
Joined
Aug 21, 2015
Messages
15
Location
Toronto
Wow, that doesn't really sound good. Glad I checked emails once more before going into the canyon lands...

I don't have a Pyrometer installed. All the gauges are the standard ones.

@greg Thanks for the chat! I learned a lot and it all makes a lot of sense. Sorry we ran out of phone credit in the end there. I'll get ready to change the pump timing on the Walmart parking lot.

I will also make the adjustments on the fan and case.
 
Joined
Jun 13, 2005
Messages
3,513
Location
Centre of the universe
Ok so here are the tools you will need
14mm wrench, gear kind are nice but not necessary and a pry tool, longer and narrow is better
image.jpg
 
Joined
Jun 13, 2005
Messages
3,513
Location
Centre of the universe
First loosen off the 2 14mm bolts on the top of the filter housing. Don't loosen any hoses. It just flops down and out of the way a bit. Don't force it, just enough to get at the bolts.
image.jpg
 
Joined
Jun 13, 2005
Messages
3,513
Location
Centre of the universe
take a pic of the two line on the side of the pump as a reference for what it's set at right now. All you need to do is move the pump side line down to retard it, it's the one on the right side. Your talking like a mm or so. Very small amount.
Important is to make sure this nut here is tight. It's the last one you will loosen as you adjust the pump timing. The pic shows the wrench on the nut. My pic shows the pump being just a bit retarded based on the stamped lines. Keep in mind these lines are only a rough reference and you should still get the engine retimed when you get back home. Retarding the timing just a bit this way is not accurate, but it's almost impossible to retard it enough to damage the engine. It would have to be so far out it would be undrivable. The short is, adjusting the timiing to retard it this way is safe. Advancing timing this way is not safe. Without knowing what your pump is set at, I'd say set your pump to look like mine. Give us a before pic tonight if you can.
image.jpg
 
Last edited:
Joined
Jun 13, 2005
Messages
3,513
Location
Centre of the universe
So first loosen off the nuts at the back and bottom of the pump, but leave the one right close to the lines tight. This is important as the pump is not easy to move sometimes and you really only want to move it a small amount so loosening the last nut while prying down on the bar you put behind it allows fine movement and you can have your hand on the wrench so you can tighten it right away. When I loosen the last nut, I only do it just enough so it's tuff for me to move the pump with the bar, and the pump often will stay in place from the resistance of the nut. If you loosen it all the way the pump will go back to where ever it feels like based on the resistance of injector lines. They are what makes moving the pump tuff.


Here is the top one, loosen it.

image.jpg

The bottom one you need to loosen is actually under the pump and close to the engine so you have to go by feel. Sorry it's a bad pic, but there is a small oil line under the pump, and the nut is just above it. All the nuts together sort of make a triangle that hold the pump on evenly. The bent crowbar feet are sort of pointing at it. You have to get the box end of the wrench on it with the wrench being almost totally vertical. Is way easier if you lay underneath the truck.
image.jpg
 
Last edited:
Joined
Jun 13, 2005
Messages
3,513
Location
Centre of the universe
Ok so the top and bottom nuts are loose and the one right beside the stamped lines is tight and you can slip your prybar just in behind the pump. In between the pump and the engine block. I'd loosely put one bolt in to hold the fuel filter out of your way while you do the adjustment. Now loosen the last nut slowly while pulling down on the prybar so as to move the pump line (right line) down and retard the engine timing. You really only need to move it a mm, but be good to post up a pic of what it's set at for us to see as you never know if it was changed before you bought it. I've bought trucks that were running pure veggie oil and the pump was advanced like 3 mm above the block line, as in really advanced.
image.jpg
 
Last edited:
Joined
Jun 13, 2005
Messages
3,513
Location
Centre of the universe
Call me tomorrow and I'll walk you through it if you like. This wount cure your overheating issue, but will give you a good safety margin for your timing. We talked about running in a lower gear and higher rpms to be safer as well which helps your engine fan run faster and the engine work less. It also lowers the negative effects of the thermal advance you experienced on your timing. The short is.... More rpms =safer for your engine.
 
Joined
Jun 13, 2005
Messages
3,513
Location
Centre of the universe
Ok so I got a better pic of the bottom nut. If your laying under the truck with yur feet pointing towards the rear and your head by the drivers front tire looking up you can get at it much easier.
image.jpg
 
Joined
Aug 21, 2015
Messages
15
Location
Toronto
Thanks everybody for your input!
Thanks Greg for that incredibly detailed instruction.

I found out that the line on the pump was about 2 mm higher, was set to an advanced timing. I have set it 1 mm below now. It feels already much better. I will hit an injection shop in Vancouver and get them to adjust the timing perfectly again. For now I'm sure I will make it through Utah without problems. I will replace my fan as soon as possible since the fluid coupling still hast too much play on the shaft (wiggles front to back). But I have sealed around the black cover to close all the gaps and prevent the hot engine air to get sucked through it.

Alright, heading out now!
Until next time and thanks again!
 
Joined
Jun 13, 2005
Messages
3,513
Location
Centre of the universe
Sounds good Marco. Glad you chimed in and described your situation in such good detail. Makes it a lot easier to help understand the problem. Look forward to meeting you. Cheers
Greg
 
Joined
Jun 13, 2005
Messages
3,513
Location
Centre of the universe
No problem guys. Just couldnt let him bang his motor to bits way out in the middle of the desert. I really felt if he lunched his motor where he was he'd be pretty much be walking away from his truck. Bad way to end a cool trip.
Later
g
 

Users who are viewing this thread

Top Bottom