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The B18/B20 is extremely straightforward -- motors just don't get any simpler than this. We'll try to warn you of any pitfalls you might encounter, so you can approach the rebuild with confidence. While the specific case described here is that of a B18 from a 122S, most of the information will also apply to other models of Volvo if you are willing to interpolate just a bit.
In this issue, we cover:
In the next issue, we'll complete the project:
Whether or not you find the process to be fun, we're sure you'll come out of it with a car that runs well and increased confidence in your abilities. Good luck!
Do you really need a rebuild?
Just for the record, there is a test which can indicate that the problem is limited to the head: squirt a little motor oil into the spark plug holes and repeat the compression test. This will temporarily cause the rings to make a good seal. If the compression does not improve, the problem is in the head. If it comes up to spec, the problem is the rings. If it improves but not enough, the engine is generally worn. Our personal experience has been that limiting the work to a valve job usually results in having to rework the rest of the motor within a year anyway, so it pays just to do the whole motor at once.
Do you really want a hot rod?
The downside of modifying is mainly the extra expense involved, even compared to replacing everything with new stock parts. Those big overbores will cost you four times the machining cost of a plain .030" over job, and leave you with nowhere to go with the next rebuild. A steep cam will require having the head machined to fit double-wound valve springs. You will have to install different needles in the carbs or increase the pressure to your injectors -- this can lead to a lot of "trial and error" before satisfactory tuning can be attained. Your fuel economy may also suffer somewhat, and the raised compression that goes with overboring will have you running premium grades of gasoline. Smog checks can also become more challenging.
Consider your driving needs and budget carefully. If you do decide that you want that extra power, there's lots to be had, and it adds little difficulty to the rebuild other than the extra machining.
For the majority of us that don't have a professional-style parts cleaner available, I recommend taking a trip to your local car paraphenalia store (Pep Boys, or whatever is in your area) and your hardware store to buy the following items:
You will need a system for organizing all the hardware that will come off the car and the motor. Zip-lock freezer bags (the kind with a label area) are a good way of keeping related parts together and identified. I also use a couple of old kitchen drawer organizers (those things that keep the knives apart from the forks) on my workbench where they won't get tipped over. I am not a fan of keeping hardware in old tin cans -- it's hard to see what's in them, and the parts tend to scatter over half the county when Bosco the neighbor's Rottweiler gets so happy about your project that he has to jump up on your workbench to congratulate you personally.
Don't start ordering parts for your motor before you take it apart and determine what you'll need, but make contact with suppliers. In my opinion, if you are in North America, your best source of rebuild kits and high-performance parts is ipd. Individual stock parts are best bought from RPR. Click on over to their websites and order catalogs from both.
Assuming your tool kit already contains a good set of sockets, extensions, combination wrenches and an assortment of screwdrivers, take a trip to your discount tool store and buy the following:
Here is a most important step: pick out a reputable automotive machine shop. It doesn't have to specialize in Volvos or foreign cars. Ask friends for referrals, and ask to be shown the prospective shop's work area. While such shops are often cluttered with engine blocks and can't be expected to pass a white glove inspection, you don't want to see tools scattered around the floor in a week's worth of metal shavings. Good shops are generally busy, so it's a good sign if lots of work is being done -- it also means you will have to wait a bit for your job to be finished, but that's a price you pay for competence. Realize also that the garage down the street gives these people a lot of work and they will be given priority over your job. Be nice to the machine shop and be patient with them -- the quality of your rebuild depends very largely on their expertise.
Finally, you will need an engine hoist and a head chain. Unless you plan on doing rebuilds regularly, it is cheaper to rent these from a local outfit than it is to buy them. Hoists either break down into pieces that will fit in a van, or they can be towed using a standard trailer hitch. Locate a place that will rent you these items by the day or half-day, and have a plan for getting the hoist to your work location.
Here is a basic rule of car repair: "It will take longer and cost more than you think." Don't let this discourage you -- it will cost less than having someone else do it, and you'll be sure of the quality of the job. Do be prepared to have some slack in your budget and alternative transportation for a month or so.
Pulling the motor is easier if you have a helper. So, if you've gotten all of the above in place and you're ready...
Section two: Removing the motor