Tips for Repairing a Chevy 235 Water Pump
If you've noticed a mess of green liquid under your truck or even heard a nasty squeal lately, your chevy 235 water pump might be on the last legs. These types of old Stovebolt inline-six engines are basically legendary for their durability, but also the toughest iron from the fifties can't fight away from physics forever. The particular water pump is usually the first thing to give out when an engine has already been sitting too lengthy or working too hard, and truthfully, it's one of those jobs you want to obtain right the 1st time so a person aren't doing this again in 6 months.
The way to Tell if Your Pump is Declining
Before you go tearing almost everything apart, it's worthy of double-checking that the particular pump is in fact the problem. Sometimes a leak appears like it's coming through the pump whenever it's actually just a loose line clamp or the cracked thermostat housing. When you discover coolant dripping directly from the little hole on the bottom from the pump casting—the "weep hole"—that's a dead giveaway. That hole will be there for a reason; it's developed to let coolant escape once the inner seal fails, stopping the fluid from getting into the bearings and causing a total seizure.
Another sign may be the sound. If you hear the high-pitched grinding or a rhythmic chirping that changes along with engine speed, the bearings inside are likely shot. You may test this simply by taking the belt off (with the engine off, obviously) and grabbing the fan blade. When there's any shake or "play" if you rock it back again and forth, your chevy 235 water pump is definitely toast. A good pump should sense solid and turn into easily with somewhat little bit of resistance.
The Short compared to. Long Shaft Head ache
One issue that trips upward a lot of people when purchasing a replacement is usually the shaft size. If you're working on a totally share truck from the particular early fifties, a person might be fine, but a lot of these 235 engines were inter-changeable into older cars or upgraded over the years.
There are basically two major styles: the "long" pump and the "short" pump. Typically the long pump had been standard on numerous of the later 235s, but when you're looking to squeeze that engine into a 1949-1954 Chevy car or an early on pickup, you'll discover that the fan sits way too close to the rad. In those cases, people often use a "short" water pump conversion or an adapter plate. If you order the incorrect one, you're heading to be staring at a lover blade that's looking to eat your rad core, and that's an expensive mistake nobody wants to make.
Obtaining the Old Pump Out
Replacing the chevy 235 water pump isn't an enormous project, but it can be untidy. You'll want to drain the radiator first. There's usually a petcock with the bottom, but if it's rusted shut—which they often are—just pull the lower radiator hose plus have a huge bucket ready.
Once the coolant is out, you'll need to remove the belt and the fan. Be cautious with those enthusiast bolts; they can be persistent, and you don't want to round them off. After the fan will be out of the way, you can get to the bolts keeping the pump to the block. On these engines, there are usually usually four bolts. Pay attention to which one goes where, mainly because sometimes they may be different lengths. In case you put a long bolt in a brief hole, you can crack the stop casting, and that'll turn a Weekend afternoon job directly into a nightmare quite fast.
Preparing the Surface
This is the part most people rush, plus it's exactly why so many new pushes start leaking inside a week. You have to get every single last little bit of the old gasket material off the motor block. I usually make use of a gasket scraper or a razor blade, followed by a light hit with some Scotch-Brite. Just be careful not to gouge the particular metal.
Once it's clear, wipe it down with some brake cleaner or acetone to get the particular grease off. You want that surface bone-dry. When this comes to the newest gasket, everyone provides their own "secret sauce. " Some men swear by using this dry, while others love RTV silicone. Individually, I like a very thin smear of the high-quality gasket sealer on both edges of the paper gasket. It helps hold the gasket in position while you're seeking to line up the bolts, and it fills in a tiny pits in the old metal.
Reinstalling the particular New Pump
When you're prepared to bolt the new chevy 235 water pump on, don't just turn the first bolt down as limited as it'll move. Thread them just about all in by hand initial to make sure they aren't cross-threaded. Then, tighten all of them in a "criss-cross" pattern to guarantee even pressure across the gasket.
You don't need to proceed crazy with the particular torque—about 25 in order to 30 foot-pounds is usually usually plenty. In case you over-tighten them, you'll just distort the gasket or click a bolt away in the block out, and then you're really struggling. Once the particular pump is upon, put the lover back on plus check your belt alignment.
Pulley and Belt Position
This is a huge offer on the 235 engines. If the pulley on the fresh pump doesn't line up perfectly with the crank pulley and the generator (or alternator), your belt will probably wear out quick. A whole lot worse, the side-loading for the water pump shaft will destroy the new bearings in no time. If this looks slightly away, you might require to press the particular pulley further on to the shaft or shim it away. It's some the "finesse" job, yet taking ten a few minutes to get this straight will save you hours associated with work later.
Finishing the task
After everything will be bolted back collectively and the belt is tensioned (you should have about half an inch of "give" in the longest work of the belt), it's time to refill the device. Don't just dump right antifreeze in there. Some sort of 50/50 mix along with distilled water is definitely the way in order to go.
Start the motor with the rad cap off in addition to let it obtain up to working temperature. You'll notice the coolant begin to circulate once the particular thermostat opens. This is when the air bubbles will burp out of the system. Watch the particular level and best it off as needed. Once the particular bubbles stop plus the level stays steady, pop the particular cap back on and choose a short drive.
Maintenance Tricks for Long life
To help keep your new chevy 235 water pump happy for the long haul, be sure you don't over-tighten your fan belt. Individuals often think "tighter is better, " but a belt that's too limited pulls on the pump shaft and eats the bearings.
Also, it's a good idea to get rid of your air conditioning every single few years. Rust and scale would be the enemies of water pumps. If the particular coolant gets dirty, it works like liquefied sandpaper on the particular internal seals. The clean system indicates a happy pump. These old Chevy engines were constructed to last permanently, and with a fresh pump plus a little little bit of care, there's no reason your own 235 can't preserve purring another fifty years.