I just broke a timing belt cauising my valves to get bent! It's gonna cost about 3 grand and I'm wondering why this is supposedly better than an overhead valve engine.
2006-08-06 09:50:40 · 5 answers · asked by bettysdad 5 in Cars & Transportation ➔ Maintenance & Repairs
An overhead cam means that the camshaft is located on the head, rather than in the block. The overhead cam design eliminates the need for valve lifters and push rods, so it is a more precise system. In some engines (V6&V8) there may be two camshafts, one operating each head's valves.
Because of the longer distance between the camshaft and the crankshaft, a rubber timing belt is used, rather than a metal chain.This eliminates the noise a chain drive would make. You do have to replace the timing belt, as part of the regular maintenance of such an engine. If you replace the timing belt at the recommended interval, it should only cost you (depending on the vehicle) $150 -$275.
On many engines the valves will get bent it the engine is run with the valve timing off, which happens when the belt is either misaligned or broken. That is what happened to your vehicle, and why the cost of repair will be so high. The engine must be taken apart, and (at the very least) the bent valves replaced.
BTW An overhead cam engine also usually has overhead valves. It is just how the valves are controlled that is different!
2006-08-06 10:11:17 · answer #1 · answered by fire4511 7 · 2⤊ 2⤋
There's no absolute requirement to pair timing belts with overhead cams, or timing chains with pushrods. The Olds Quad Four used a chain to drive overhead cams, while Kawasaki has a few overhead cam motors that use a gear and shaft drive. The reason for timing belts is that they make less noise and vibration.
2006-08-06 12:02:43 · answer #2 · answered by Mad Scientist Matt 5 · 0⤊ 0⤋
the main benefit is less moving parts, more precise control of the valve-train, most engines with timing belts are due to be replaced in the 60000 - 70000 mile range or unfortunately you can end up with damage
2006-08-06 10:00:03 · answer #3 · answered by Kato 3 · 0⤊ 0⤋
OHV engines have more speed as there is less frictional loss comparesd to the conventional valve opening mechanism with a push rod. yes they are xpensive to maintain..
dr. stan
2006-08-06 09:58:04 · answer #4 · answered by icemaiden 2 · 0⤊ 0⤋
less parts and friction, higher rpms, better efficiency. 3 grand sounds steep though
2006-08-06 09:58:33 · answer #5 · answered by Christian 7 · 0⤊ 0⤋