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BJ-7 head reinstallation.

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robert_ellison

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I will be removing the head on my BJ-7 for inspection as it has sit for a number of years (22) and I wonder what I should be looking for as trouble spots, and if there are any, if I can fix the problems myself of need to have a shop do the repair?

The engine was completely overhauled 22 years ago and hasn't been started, or turned over, since.

Also, when reinstalling the head is it necessary to install a new gasket?
 
Yes to the gasket replacement, but why do you feel you need to pull the head?

If the engine has sat since it was overhauled last, and you've kept it oiled periodically, I'd fire it up and evaluate the condition that way.
 
Well, in another thread I was advised that even though I squirted oil into the spark plug openings and poured it over the rockers and into the openings beneath the rocker cover, the fact that I never cranked it over or started it for 22 years would possibly create rust

GregW
"Maybe I'm overly cautious, I think 22 years is too long. While you have been adding oil to the cylinders, the oil is only working on the cylinder from the rings down. So a piston at BDC isn't oiling much of that cylinder. The solid lifters are keeping a couple valves open to the atmosphere, so some moisture is getting in. The valve faces in the head may have rust on them. Water pump should be checked to make sure it isn't seized, hand turning would work. You may find some gaskets have dried out. I agree with Greg Lemon about pulling the tappets to lube the cam again. If it was my car, I'd pull the head for inspection as a minimum."

So...?
 
Check the compression before you remove the head. I wouldn't think sitting would cause any problems as there was no heat to warp or water to corrode. I found on my BJ8 that the PO had done a poor job of resurfaceing and left ridges on the head which caused a seeping oil leak but she ran beautifuly with good, even compression. These are tough engines that run in spite of us. I'd think the big precaution would be scoring the cylinder wall without good lubrication when you first start her up.
 
robert_ellison said:
I will be removing the head on my BJ-7 for inspection as it has sit for a number of years (22) and I wonder what I should be looking for as trouble spots, and if there are any, if I can fix the problems myself of need to have a shop do the repair?
Click to expand...
Hi Robert,
The things I'd look for are rust in the upper areas of the cylinders, and corrosion in the valve area. The valves and seats were probably never oiled when the engine was reassembled. (The inside walls of the crank case probably weren't either, but any rust there should wash down into the oil and be filtered.) I'd check a couple valves to ensure that they haven't seized in the guides. Is it <span style="font-style: italic">really</span> necessary to do? Most people who have responded think not. With no disrespect intended, I think it is an expensive gamble. As I said in my first reply, it is what I'd do if it were my engine. One note about the compression check, the engine would have to be turned over several times to get the readings. Here is a photo I took of a float bowl. I had this carb for about a year and a half before using it, brand new. Just the moisture in the air made me rebuild it.
 
robert_ellison said:
thanks Greg.

If there is corrosion do I have to have a shop do the work or can I clean it up?
Click to expand...
Rust on the surface you can deal with; pits below surface would require honing (still not beyond diy) or more likely, an overbore to the next piston size.
 
robert_ellison said:
thanks Greg.

If there is corrosion do I have to have a shop do the work or can I clean it up?
Click to expand...
I'd take it a step at a time Robert. I'm not saying there <span style="font-style: italic">is</span> a problem. I'm saying it's better to make sure you <span style="font-style: italic">don't</span> have a problem. If there is anything you find out of sorts that you have a question about, ask here and/or post a photo. If everything looks good, fire that baby up!
 
Randy is usually right. I wouldn't pull that head just to "look". Oil it up again, do the other normal maint / prep and fire it up. No harder to fix after the fact, if there is a problem, then to fix it before. My 100/6 was very similar to yours. No miles between rebuild in 1983 and driving in 2008. Probably a couple hours running time between those two dates. Smoked like the devil for an hour or two on initial start last year and then everything was fine. Bob
 
I would pull the head and the oil pan{bearing clearance,oil pump} to check everything.Those 22 yr old parts are probably ok,I would rather spend the $$ to insure that I don't have to put in any NEW parts[In Light OF Recent Quality Issues],and I would have the valves cut w/ the 3 angle seats.Water pump,oil pressure relief spring,check the dizzy drive for direction,etc.The inherent value of the car would be enough for me to do this,what's a few more weeks after 22 years? Also ,what if you DO find a problem? Your time and $$ will be well spent...Your motor mounts may be crumbly by now,and of course all rubber hoses, fuel lines, don't expect points or condenser to be any good either.Carbs need to be checked,trans mounts,all electrical grounds,there is a lot to do..If the rebuild was done right,you will have many years of pleasure at a minimum cost relative to starting over if something fails from sitting too long...
 
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