I'm having one of those days :(

This concerns my 1980 Volvo DL (240 N/A) with about 143k miles (odometer broke). I read the FAQs carefully.

https://www.brickboard.com/FAQ/700-900/Cooling.htm

Questions:

It's hard to find water pump gaskets (my water pump is fine, just needed a new gasket and o-rings). I had a leak and tear with auto store-recommended gray (rubber-fiber). What's the best gasket material to use and to avoid?

Also, you're not supposed to reuse the water pump bolts, but I'm having trouble finding replacement bolts, absent buying a new water pump. It looks like the bolts are M6 maybe 30 mm and 8.8 strength. I'm reluctant to buy regular bolts at Home Depot. Can anyone confirm the specs and place to buy them and/or other components of 240s that I could get from junkyards?

Are B21F water pumps harder to install than B230F? This is my experience. I changed a water pump on my 1988 240DL in a couple of hours, start to finish. I spent nearly 12 hours just trying to install the water pump without leaks. I followed the FAQs carefully.

Here's what's going on.

According to brickboard FAQs (see link above), I'm supposed to install the water pump straight into the engine block, then loosely attach the two nuts on the right, then use a lever to push up the water pump while installing the bolts. I tried that at least 3 times only to get the water pump's upper o-ring to compress funny and to leak. I *think* that I solved the problem by putting one bolt on the top left in as a guide, then used a putty knife to flatten and align the o-ring. Thoughts about how to do this properly if the FAQs don't work?

The upper water pump o-ring was swollen and had oil over the top, indicative of a camshaft oil leak. When I removed the o-ring, it was not really swollen, but had cuts across the top. What caused that?

"...I'm supposed to install the water pump straight into the engine block, then loosely attach the two nuts on the right..."

It sounds odd that you would use two nuts on the same side of the pump in order to hold the pump square up against the bottom of the head. If you look straight at the pump you should find that two holes are slightly elongated vertically, while the other three holes are round. It's the two elongated holes whose nuts are loosely installed and then snugged while prying upward on the pump. The two elongated holes should be on opposite sides of the pump as I best recall. You just snug those two fasteners enough (not fully torqued) to keep the pump from sliding down while the other three bolts are installed. I have had the best luck just coating the gasket with a very thin layer of axel grease, rather than gasket adhesive, so that the pump can slide upward without buckling/tearing the gasket.

Before you install the pump hang it on the engine with all five fasteners screwed in finger tight and then backed out a turn or two. Make sure you can then slide the pump all the way up against the underside of the head. If it won't slide all the way up figure out why. You may have to clean up one or more bolt holes with a rat tail file. Some of the pump castings are horribly messy!

Also, before installing the pump, make note of how far the O-rings extend above the pump's upper surface. Then after the pump is installed and tightened take a feeler gauge and measure the gap between pump and head to verify that the the O-rings have been substantially compressed. No sealant on the O-rings.

If the old bolts/studs aren't so deeply rusted that they appear to be weakened, then you should be OK to stick with them. Often times a 40 year old OE bolt is better than a brand new one from Ace Hardware, even if grade 8+.
--
Current rides: 2005 Volvo S80 2.5T, 2003 Volvo V70 2.4NA, 1973 Volvo 1800ES (STILL not road worthy!)

Thanks.

I looked at my 1988, but can't see (or recall) most of the water pump bolts vs. studs without removing the water pump pulley.

On the 1980, there are 2 bolts on the upper left (one holds the return line), 2 bolts on the lower left, and two studs with elongated holes on the right. I thought that arrangement odd, too, because the FAQs emphasized tightening everything equally in a star formation.

The water pumps for the 1980 and 1988 are similar, the only difference being the location of the bolt that secures the return line, 1980 being on top, 1988 on bottom, making them incompatible unless I somehow figure out how to invest that bolt.

All of my water pump bolts are starting to round out (I used 6-point sockets only), but I cleaned the threads and used anti-seize, so hopefully they'll come out easily next time I do the water pump. I have a spare water pump pulley nut, which is M6 x 1 and it fit perfectly on the studs of the water pump stud, so I presume that the bolts must be M6 x 1 x 30 mm.