LUVTruck.com

ok, so i brought my new Luv home last night, and i already knew that it would require a head gasket to be replaced. however, i just want to confirm my suspicions. its a small leak,(and so far the only one i see)

Just under the no.'s 3 and 4 cyl


Close up




also, ive noticed a large amount of oil on the engine and underneath the hood itself. any thoughts?

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To the Oquirr hills for awesome thrills! Go-go 4wd, Activate!

I think you may need more than just a new head gasket.

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1980 4x4 KBD40 ISUZU/Chev Luv
Factory Fitted c190 Diesel Engine, ARB BullBar, Ramsey Winch, Custom Tilt Tray,

With that much oil sprayed everywhere could be blow by. You might need a set of rings. If you're that far into it you might as well go with rod and main berings as well. Run a compression check and that will tell you alot. The compression will naturally be a little off on the cylinders where the head gasket has problems but the others might give you an accurate reading.

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In life there is the "Way things should be" and then "There's the way they are".

2005 Silverado 3/4T Crew Cab
1981 Luv 2WD
1979 Luv 4x4 Currently going through Open Heart and Cosmetic surgery
1995 Roughneck JetBoat
1981 Luv parts trk

well, after cleaning everything up, the coolant level has remained almost consistent, and ive only added about 1/2 cup since i cleaned everything. i know the carb is in for a rebuild as evident by the grime on the outside of it, but beyond that, i think its been a case of sitting for a while that has made the truck leak. im still going to replace the head gasket, but at least for now, so long as i keep an eye on the temp gauge, and keep checking the coolant level,im hoping to put that off for a bit.

as far as the oil goes, there is no oil on the air filter, and no new oil is under the hood, which im thinking is a good thing, but it does beg the question as to how it got there in the first place. i havent noticed any other leaks, but i did notice that the steering gearbox has some built up grease on the top cover.

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To the Oquirr hills for awesome thrills! Go-go 4wd, Activate!

Make sure you keep a good check on your oil level and there is no coolant getting in it. A blown head gasket can cause coolant to leak into the pan.

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In life there is the "Way things should be" and then "There's the way they are".

2005 Silverado 3/4T Crew Cab
1981 Luv 2WD
1979 Luv 4x4 Currently going through Open Heart and Cosmetic surgery
1995 Roughneck JetBoat
1981 Luv parts trk

what your seeing is quite normal. I doubt its an actual blown head gasket.

I bet you have a seeping head bolt or a high spot on the deck right there. Ive seen this alot when the stock replacement Steel Shim style of gasket is used and have really seen it on the cheaper orange/black felpro head gaskets.

I set of GM head coolant tabs or Moroso ceramic block sealer should cure it.

A.j.

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http://www.youtube.com/watch?v=ykgDNjeTa0g

i see... well from the picture, its a bit hard to tell now that i have cleaned the block at the local car wash, but im still seeing it seep out. so far, i've not seen anything in the oil pan, but i was questioning the use of a block sealer only because of the crud i have to deal with once i do decide to do a rebuild. come to think of it, ive never heard of moroso producing a ceramic sealer

(i guess you DO learn something new everyday!)

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To the Oquirr hills for awesome thrills! Go-go 4wd, Activate!

LOL no problem, I deal with seepy head gaskets alot on my Buicks, It has alot to do with the 4 head bolts per cylinder, Im not to sure on the Isuzu motor for certain, but the threads almost come to the top of each bolt boss- this causes the deck material to distort and pull up. Which leads to that seepy gasket. When the head is off, we take a mill bit and machine the threads about an 1/8 to 3/16" deeper from the deck, This helps to prevent that distortion. This is a common mod to alot of pre 1985 engines.

Summit carries the Moroso Ceramic Block seal, good stuff... but is NOT compatable with antifreeze, so I gave you the link for the right stuff.

http://www.summitracing.com/parts/MOR-35520/?image=large

Hope this helps!
A.j.

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http://www.youtube.com/watch?v=ykgDNjeTa0g

well, after much debate and saving to get the head done, i put my engine back together and i'm STILL getting a leak between the head and the block. and in the same place too!

the head was machined and we double checked it prior to install. i did notice that before i did the head, it wasn't exactly running hot, but the temp would spike and then resume to normal. i replaced the thermostat with a 180 deg one, and its still doing this ( i had believed a sticking thermostat was causing this)

so now my question is.... what do i do now? i can drive it, but i wouldn't take it too far....

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To the Oquirr hills for awesome thrills! Go-go 4wd, Activate!

Temperature spikes can be caused by alot of issues. Does it just go up in temp once a little higher than normal? Mine usually goes up a little past the first line the first time I start it after it sits for a while, (over night, all day at work) but then comes back down and stays there the remaining time while driving, in town, on the highway, up and down hills. Does yours just spike once and then come back down? Does it do it over and over? I had this issue with my '81 a while back and it started blowing the fluid out the overflow hose. I replaced the Radiator cap and no more problems. The old had no pressure remaiting in the spring and the gasket was shot.

How clean is your radiator? What does your water flow look like when its hot? Just some things to look into. Good luck.

_________________
In life there is the "Way things should be" and then "There's the way they are".

2005 Silverado 3/4T Crew Cab
1981 Luv 2WD
1979 Luv 4x4 Currently going through Open Heart and Cosmetic surgery
1995 Roughneck JetBoat
1981 Luv parts trk

Now that you had the head machined that should eliminate that. I supect you need to plane the block surface flat again.
I have run into a number of Luv blocks that pull up and distort around the head bolt threads, probably caused by over torqueing the head bolts in the past in an attempt to stop a leak. I also suspect this is a weak area with the Luv block.
I always torque mine to 55-60 ft lbs, not 70 like recomended. No problems sinse then.
The heating up spiking is usually caused by air in the cooling system from the leaking, non sealing head gasket. However a sticking thermostat can also do this so eliminate that first.

The engine in my truck is a semi-fresh rebuild (30,000 mi), and it has done the whole oil all over the hood thing before. For me, it was a leaking valve cover gasket. Oil would leak out the front of the valve cover, onto the pullies, and then get sprayed onto the hood. Driving along made the oil flow backwards along the hood... hardest oil leak I've ever tried to find.

I think this is what your problem was, and if you replaced the head gasket, you likely replaced the valve cover one, fixing the problem. BUT, beware the neoprene gaskets. They tend to shrink and cause leaks (at least in my experience), so I put a cork one in this time. No problems since.

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1980 4X4 LUV daily driver, as stock as can be.

Well, the temp spikes slightly right of the first notch then drops to a more normal temp. the rest of the time while driving, (like yesterday while going to my photoshoot) it will drop and then will climb ever so slowly until the needle is just before the notch.

this is when i usually turn on the heater and it comes down a bit.

Utah has alot of highway here so im usually driving at 55 or so.

I have also noticed that im losing coolant through the overflow hose and have since added a coke bottle to catch it. its not ALOT, but its leaking enough to make me worry. im thinking that if i replace the radiator cap at this point, the excess heat will cause the coolant to shoot out through the same leak between the head and the block.

im going to check the block again, but i remember when i pulled the head, we checked it with a straight edge and it was perfectly flat.... do you guys know if the studs are supposed to be replaced when a head job is done?

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To the Oquirr hills for awesome thrills! Go-go 4wd, Activate!

So, a kinda silly question... did you torque the head bolts in the right order? Sometimes torquing stuff in the wrong order can cause gaps...

Uh, that kinda sounds normal to me... your temperature spikes might be the opening and closing of the thermostat. When the cold water from the radiator hits the engine when the thermostat opens, the temp should drop, and when the thermostat closes, the temperature should rise again. My truck seems to run the best with the temp needle at the little gap in the line (about 180). Maybe measure the actual temp with a thermometer?

With the losing coolant via the overflow, that's normal too. With your Coke bottle, fill it about 1/4 way with coolant, and make sure the overflow hose is close to the bottom. While you're driving around, your coolant gets hot and expands, creating the 16 psi that the system runs at (it should say this on the cap), and the radiator cap should act like a regulator. When the pressure gets above 16, it opens, bringing the pressure back down to 16, releasing some coolant in the process (to some sort of reservoir, a Coke bottle in your case). When the truck cools down (this is the important part IMHO), a vaccuum is created, which opens a one way inlet valve in the radiator cap, pulling the coolant back out of the reservoir. On the most important point, if this vaccuum gets big enough, it will start to crush sections of your radiator (heater core too) or collapse your coolant hoses.

Please correct me if I'm wrong. Definitely always willing to learn.

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1980 4X4 LUV daily driver, as stock as can be.

That's a very good explanation and well put together. I have to say my Radiator cap seemed to go bad in a very short amout of time and that is when I started losing coolant. Since I have replaced it I have rarely had to add any coolant. With the new thermostat and if he installs a new radiator cap that should be sufficient to keep the system closed. If he were to start really working the truck hard...towing something fairly heavy (heavy for a Luv anyway) or hauling a load and maybe pulling a hill or two while doing this then I can understand it heating a little above normal and the cap allowing some coolant to blow out through the overflow hose. If your system is allowing coolant to escape to the point that you are having to add coolant daily or even weekly something is definitely wrong. Typically you shouldn't have to top off the system no more than every 3,000 miles when you do an oil change and that should be minnimal. I change my oil every 4,000 miles and check all my other fluids then as well. I practically never have to add any collant. Very little if any. With that said, nothing is perfect with these little trucks and I to have considered adding an overflow tank to mine as well just to make sure I never have a problem. That's what I think anyway, I can definitely be wrong on this.

I would try the new cap. If you start spitting fluid from between the head and block again then you have other problems that need to be addressed. If fluid can leak out through the head gasket then air can get in causing your system to get bubbles in it and also cause the problem you are having.



That's how mine runs. It will climb slightly past the first notch on the temp gage (about the width of the temp needle) and then fall back to about 2 widths of the needle under it and remains there. The only difference is I haven't lost any fluid....well not since I replaced my cap that is.

Good luck and keep us posted on what you do and how this turns out.

_________________
In life there is the "Way things should be" and then "There's the way they are".

2005 Silverado 3/4T Crew Cab
1981 Luv 2WD
1979 Luv 4x4 Currently going through Open Heart and Cosmetic surgery
1995 Roughneck JetBoat
1981 Luv parts trk

Hmm... yeah, the main pressure regulator spring sounds a bit shot. lol, forgot about that. I suppose that's what I get for posting so early in the morning.

I was also told that replacing your cap could make the weakest part of your system burst from the increased pressure, so if you haven't replaced your coolant hoses recently, now would definitely be a good time (especially with the oil leak that sprayed oil all over the hood. Oil and rubber hoses aren't friends). Maybe give your radiator a good once over too, if you haven't already.

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1980 4X4 LUV daily driver, as stock as can be.

Once again you are right. After I replaced my cap it wasn't a week later my bypass hose blew up on my way home one night. The same night a Whitetail Buck decided to committ suicide and run into the side of my truck at 60 MPH. I drove home with a dented passenger door, side of my bed and about three miles from the house my hose blew and I had to stop and let it cool down, poor what water I had in it from a couple water bottles I had and then limp it home with the cap cracked loose.

Figuarus, if you replace your cap make sure you inspect your hoses....all of them including the heater hoses and watchout for Suicidal Whitetail Deer LOL.

_________________
In life there is the "Way things should be" and then "There's the way they are".

2005 Silverado 3/4T Crew Cab
1981 Luv 2WD
1979 Luv 4x4 Currently going through Open Heart and Cosmetic surgery
1995 Roughneck JetBoat
1981 Luv parts trk

well, at this point, im going to have to pull the head AGAIN, and find out what happened. i torqued the bolts down in a cross fashion. ive checked all the hoses for weak spots and it looks like someone has replaced them not too long ago. (they still have the part no. tags on them)

dunno if i mentioned this, but i already replaced the thermostat prior to changing the Cyl head gasket.

im going to have to wait at least 3 weeks before i can pull the head, but when i do, ill make sure to take pictures along the way. maybe i did something wrong.......

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To the Oquirr hills for awesome thrills! Go-go 4wd, Activate!

Since you're planning to pull the head again why not gamble $5.00 at NAPA for a new radiator cap and see if it makes a difference. Might tell you something before you tear into it.

Just to make sure I'm right....it spikes up once a little beyond the first mark then comes back down to it's normal spot and stays there. Am I right on this? As of right now you don't have any coolant leaking from the head gasket? You do have fluid spouting from the overflow hose.?

You have replaced your head gasket and thermostat.

If I am right on this why not spend an hour and re-torque your head bolts and replace your Radiator Cap? A little bit of labor and about $5.00 or so will tell you alot before you get into. If it does start losing fluid out of the head gasket again you probably want to have your block checked. I would eliminate all possibilities before I tore into it AGAIN and have as much info as I could. If the new cap causes it to start leaking again from the head gasket you can always put the old cap back on until you tear it down and put in a can of stop leak to help out if needed until you're ready.

If you end up having your block surfaced make sure you have the same amount taken off your front cover as well.

_________________
In life there is the "Way things should be" and then "There's the way they are".

2005 Silverado 3/4T Crew Cab
1981 Luv 2WD
1979 Luv 4x4 Currently going through Open Heart and Cosmetic surgery
1995 Roughneck JetBoat
1981 Luv parts trk

The only thing that I can pick out that you might have done wrong is the torquing order for your head bolts. It's kinda specific. the order is in Chilton's, and I know I've posted it on here once before, but I can't find the post.
If you need the info, I'll post a scan of the page... tomorrow.

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1980 4X4 LUV daily driver, as stock as can be.