Quote:
: My car has been plagued by an overheating
: problem. After going through all the cooling
: system accessories I finally pulled the
: head.
: Here are my questions
:
: 1. Which was more likely to contribute to the
: overheating? The carbon buildup or the
: partly plugged water passages.
: problem. After going through all the cooling
: system accessories I finally pulled the
: head.
: Here are my questions
:
: 1. Which was more likely to contribute to the
: overheating? The carbon buildup or the
: partly plugged water passages.
**Plugged water passages, including a "too small" radiator. (Kinda acts like a plugged passage if you think about it)
:
: 2. Were the wire rods put in at the factory. My
: friend and I came up with three possible
: explanations: (a) they were placed there to
: prevent corrosion in the head (sacrificial
: metal) - not likely in my opinion because
: they weren't corroded. (b) they were placed
: there to prevent the water passages from
: becoming plugged up. (c) assembly line
: hi-jinks. (d) none of the above.
** The answer is (d), those are old casting "core wires". These wires helped the foundry workers hold all the waterjacket sand cores together as the sand molds were made & the mold poured. Pull them out whenever possible.
:
: 3. I noticed that there is a water passage at
: the front of the head/block that is blocked
: off by the head gasket. Why? What is the
: reason for this? Better coolant circulation
: in the head? What would unblocking it do?
** The cool water comes-into the block at the waterpump, most of it is suppost to flow through the block, cooling all the "barrels", then come-up into the head through those two large holes and flow forward. (a small amoult of cooler block water comes-up under each exhaust port through the small "steam holes", see diagram, cooling passages (6)directly accross from all the exhaust valves)
If you open-up that front or even the middle passage, the water flow will "short circuit" from the pump area, up through this hole and right back out into the radiator, without cooling the engine. This will "fool" your temp. guage to show "cold"(awash with cool water directly from the radiator) as the rear of the engine "frys".
I do admit that the factory is not real clear on this and even this diagram implies that the front passage is open but Leave it Closed! The only gasket "mods" under review by the racers is to enlarge the steam holes and put an additional stem hole at the middle point in an attempt to even-out the head temp, front to back.
DD
