Volvo Penta raw water pump

What do i actually do if my motor is overheating?

There are three typical reasons why marine machines overheat. 1) minimal circulation or no movement of raw water (either lake liquid or sea water); 2) Lack of blood flow of engine coolant or anti-freeze; and 3) Compression gases or atmosphere in coolant system.

1. The outward symptoms of low flow-on your natural liquid cooling circuit are usually described as a sluggish overheat. The motor will most likely keep heat at reasonable RPMs, but will quickly gradually overheat at higher RPMs. An excellent place to begin is with your natural water or impeller pump. Search for broken or missing fins regarding rubber impeller. The second location to seek out restrictions is regarding the intake region of the pump. Any coolers (such power steering coolers, transmission coolers) tend to be suspect. These coolers tend to be an excellent place for dirt, grasses, etc., to restrict water movement to the engine. In the event that intake side is located free and obvious, be sure that all hoses and hose pipe clamps tend to be tight and undamaged to ensure no air is introduced into the system through a loose fitting or a deep failing hose.

a limitation in the socket side of the raw water pump will cause reduced flow and overheating because the natural water cannot exit the engine quickly enough to get rid of the temperature. And so the amount of water moving through motor is decreased. A typical place for this to take place is on fatigue risers or elbows in which build up when you look at the liquid passages are restricting flow.

A "no circulation" of natural liquid is usually caused by a failed raw liquid pump, a negative pump impeller or a significant suction drip in the intake region of the impeller pump which preventing the natural water pump from picking right on up any liquid. The symptom of this kind of overheating issue is usually a fast spike in heat where you can actually watch the temperature gauge increase.

2. If you have a closed-circuit coolant system in your motor (your motor calls for anti-freeze) then your air conditioning issue might be brought on by not enough flow or no circulation in the engine coolant system. Check to make certain that the belts driving the blood supply pump tend to be undamaged and therefore the blood flow pump just isn't leaking liquid from the “tattle-tale” gap on the underside for the pulley shaft installation. If these items are observed become ok, then next many logical destination to check always could be the thermoregulator. If a thermostat is stuck shut, it'll trigger a spike in temperature from normal running range. The engine will work typically until it hits the proper operating temperature. The gauge continues to increase rapidly beyond that heat.

Dirty heat exchangers are a common issue on closed circuit air conditioning systems. Symptoms related to a dirty temperature exchanger are generally a slow overheat that increases with engine RPM. Instance: your engine will preserve normal heat at 2500 RPMs but will quickly slowly overheat at 2800 RPMs. The cause of here is the build up of “sludge” on heat exchanger which impedes being able to dissipate heat towards raw liquid system. Heat exchangers can generally speaking be cleaned by your regional radiator shop or by a light answer of muriatic acid, (like that regularly clean concrete) offered by many equipment stores. Please be aware that you might perhaps not utilize this strategy in case your heat exchanger is made of aluminum! Utilize careful attention using this acid: it is harmful to your eyes, skin and creates powerful vapors.

3. Air or compression gases inside coolant system may cause overheating due to the fact that environment is an unhealthy conductor of temperature. Air within coolant system may also cause your blood supply pump to give up. (Circulating pumps circulate antifreeze.) Centrifugal pumps cannot pump environment. Air has the coolant system through leaking blood supply pumps, bad hoses, loose hose clamps regarding the suction side of the pump, and/or because of the engine it self by means of compression fumes. Most people would refer to this as a bad head gasket. Example: a poor head gasket enables compression stress from piston cylinder to locate its means in to the cooling system. These fumes are extremely hot and permit air to the system which in turn causes the engine to overheat. There are various places in which motor fumes or compression fumes can go into the system, the most typical becoming the head gasket. Another places that compression fumes can come from tend to be cracked cylinder minds, cracked blocks, or fatigue manifolds. There clearly was a chemical test open to check for compression gases inside coolant system. Contact your neighborhood auto components shop for a chemical testing kit.

IMPELLER TALK by Bob Van Brunt

The reason why did the impeller in my own pump lose their freshness?
How many engine hours should it final?

The ocean water pump is an optimistic displacement pump. They've better suction compared to centrifugal pumps, and also you don’t need prime them. These are generally used for all sea liquid air conditioning programs. About 500 motor hours is the average-life of an impeller. The Volvo Penta impellers are constructed of neoprene plastic. There are several aftermarket impellers (blue in shade) that are designed to operate much longer dry without damage.

Look at your impeller ahead of spring commissioning in the pre-launch maintenance. Choose splits at root of the fins and for missing fins. Any of these flaws warrants replacement of the impeller. Loss of air conditioning water due to a damaged impeller could cause serious and expensive engine harm.

An impeller may go bad early because it is run dry. Either a through-hull ocean device has shut, or a-sea strainer has blocked. You need to have a hull strainer and a-sea strainer with a removable basket on your own watercraft. When they do not get water, they will burn-up in about 30 seconds. Ensure your valves are open and that your strainers are clean before going away.

The circulation pump is a centrifugal pump. This has a metal impeller that pumps cooling fluid (jacket water or anti-freeze) through motor. In case your blood supply pump is dripping substance through the “tattle-tale” gap, found just underneath the pulley and shaft construction, you have a negative seal as well as the pump should be replaced. Another problem that arises with blood supply pumps could be the failure of shaft bearings, often evident from a rattle or “squeal” from water pump location. The pump bearings may be examined aided by the engine shut-off by examining the action in the pump pulley. There should be almost no, if any, up and down activity. Many people exchange circulation pumps convinced that it's going to resolve an overheating issue. This a typical blunder. If the pump bearings tend to be fine in addition to seals are not dripping, there's a good chance that pump is okay.

PROPPING BASICS by Scott Huber

The goal of a propeller is two-fold: the very first is to move the boat, the second is to properly weight the motor. The first, people comprehend, the 2nd, a lot of people don't understand.

The maximum accessible RPMs of a marine motor is actually determined by the size...