VP2003 o'heating again

vic008

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Trouble again/still. Blew the g'box to impellor hose apart. Steam! She was leaking at the riser base, then stopped leaking there two days later (yeah I had removed riser to get new exhaust hose on.) Riser looked clean- can test by pouring water down a hose on end of the copper tube.
Was wondering, does the water distribution pipe in the head give any trouble? Easy to remove? Thanks
 
It is difficult to understand why sufficient pressure built up in the inlet pipework to blow it apart, after all it;s open at the inlet end. I think you need to check the inlet plumbing right through from the skin fitting ( and strainer grid on the outside ??) . through the seacock, strainer and gearbox cooler including the hoses to the water pump for blockages and obstructions

It is also difficult to understand why the system pressurized that much anyway when its open to the exhaust system at its back end. Therefore check all the hoses and rigid pipework around the engine and the injection point into the exhaust. Especially the latter.

It would be a good idea, if not already done, to check the pump for wear, fit a new impeller if ok , and to check that the thermostat opens over the specified temperature range. (Bgins to open at 60C, fully open at 75C)

Also probably a good idea to remove the water distribution pipe in the head and check it, at least the holes that allow water to flow from it into the head . I don't remember if it has to be correctly orientated when refitting ... therefore check what the workshop manual says about it
 
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It is difficult to understand why sufficient pressure built up in the inlet pipework to blow it apart, after all it;s open at the inlet end.

I agree, it doesn't make any sense. One possibility might be that the inlet seacock is jammed shut, despite the handle moving.
 
You did not say which 2003 you are having, direct or indirect cooling.

I had big trouble with my 2003T. It turned out that the previous owner dropped a a gasket into the internal cooling system. on the 2003t is on top a pipe which goes to the thermostat. This pipe has internal a shim which reduces the 15mm diameter to about 3 mm. This 3mm opening was clogged up several time with little pieces. We applied a hose connected to a dive bottle (200bar) to the place where the normally the Thermostat sits,….had a net on the place where the water goes into the exhaust. When we pieced the pieces together it looked like a 1 Inch gasket….
Now the engine runs for two years without any problems. Temperature is absolutely stable 74 plus minus 0.5 degrees, even over 10 hours….I have a digital cooling water display…the temperatur is unbelievable stable.
 
A few possibilities spring to mind. One is that the exhaust elbow water inlet is blocked. It happened to me not long ago. I was able to clean mine by removing it and soaking it in brick cleaner If it's really knackered, you can get a new one from Keyparts. Another is that the impeller - the current one or a past one has shed a vane or two and they're blocking things. My final idea is that, with a raw water cooled engine, a buildup of crud in the engine is blocking the passages. Ridlyme (sp?) is, I understand, the appropriate cure though, being a tightwad, I'd probably get out the brick cleaner again.
 
.......the impeller .... has shed a vane or two and they're blocking things. My final idea is that, with a raw water cooled engine, a buildup of crud in the engine is blocking the passages. ......... I'd probably get out the brick cleaner again. /QUOTE]

+1 That's exactly what caused my recent overheating. I found a fragment of pump blade had lodged at the input to the 'flute'. Crud had grown around it during my ownership and eventually blocked the cooling water input to the engine completely. I did a full engine flush with brick acid, including the engine block drain valve. (There was no need to remove the flute)
Cooling water throughput is now remarkably improved.
Cheers
Bob
 
Yesterday took the delivery hose from impellor pump off , ran engine, and water flows good. So that takes water to delivery pipe (with holes) thru head and out back end, thru another short pipe and into the riser to mix with exhaust. No water goes manifold to riser thru those 4 slotted holes right?
 
Yesterday took the delivery hose from impellor pump off , ran engine, and water flows good. So that takes water to delivery pipe (with holes) thru head and out back end, thru another short pipe and into the riser to mix with exhaust. No water goes manifold to riser thru those 4 slotted holes right?
When the engine is cold water flows as you have described; from the water pump to the distribution pipe, right though this and then via the pipe at the rear of the engine into the exhaust outlet elbow , or the riser if you have a riser .

When the engine is hot, and the thermostat opens, water also flows from the distribution pipe into the cylinder head to cool the engine. Hot water leaves the engine via the thermostat and flows along the pipe above the cylinder head to the exhaust outlet elbow or the riser.
 
Just got riser off, and the slotted holes are jammed closed. Should these holes be open? Is this my trouble?
Almost certainly your trouble. Also check the water pathways in the elbow. The water passages in the engine may also be blocked
 
Think with the sound advice above, you may have sorted it out. Hopefully. Just perhaps be very aware that any sort of air intake on the low pressure suction side of the water pump will cause such a similar result. Even something as simple as the intake filter housing gasket or lid being poorly sealed, will cause such a thing.
 
Hi I am not sure if this has already been mentioned, in the thermostat housing there is a small hole which has a pipe attached to it this goes to the header tank it is a breather if this is blocked it prevents water circulating around the head took me ages to find this after many hours trying to stop over heating.
Mike
 
Hi I am not sure if this has already been mentioned, in the thermostat housing there is a small hole which has a pipe attached to it this goes to the header tank it is a breather if this is blocked it prevents water circulating around the head took me ages to find this after many hours trying to stop over heating.
Mike
Header tank ? ...... It's a seawater cooled engine ... . I think
 
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Raw water cooled.Backing the truck up here. No, no, the 4 slotted holes are not to pass water. The only water to the elbow is delivered by the 2 pipes.( from google) Today hope to get delivery pipe removed. Otherwise must be the elbow at fault.
 
Raw water cooled.Backing the truck up here. No, no, the 4 slotted holes are not to pass water. The only water to the elbow is delivered by the 2 pipes.( from google) Today hope to get delivery pipe removed. Otherwise must be the elbow at fault.

I wish you luck with the removal of the soft copper pipe located in the head.

I tried to drift it out but had to stop.

In the end, I fashioned a knitting needle , and bent the sharp tip to a right angle. Then, by feel , located the holes in the pipe shining a torch at one end while having a really good poke at the holes with the needle. That did the trick.

It's very important to make sure that the pipe is marked before removal to make sure the holes are in the correct plane.
 
Raw water cooled.Backing the truck up here. No, no, the 4 slotted holes are not to pass water. The only water to the elbow is delivered by the 2 pipes.( from google) Today hope to get delivery pipe removed. Otherwise must be the elbow at fault.
But if there is a riser water from the two pipes is delivered to the riser then it flows via these water channels in the riser into the elbow.
Water only flows directly from the two pipes into the elbow if there is no riser

Are you now saying after talking about the riser right from the beginning of the thread that you do not in fact have a riser ?

To make things clear refer to the parts diagram and you will see #29 is the riser which may be fitted below the elbow #1

11039.jpg
 
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.....Today hope to get delivery pipe removed.
Terminology may be causing some ambiguity in this thread - my comment here refers to the removal of the multi-bend pipe between the rear of the 'flute' and the exhaust (8 in Vic's diagram above).
1. Be careful not to lose, if fitted, the reducing plastic insert into the rear of the flute. It is a loose insert and reduces the pipe diameter to 6mm. This item is not shown on any VP diagram that I have seen but both my RW 2003 had one. (Best guess to date is that it is fitted to balance the water flow in the two paths described by Vic, when a calorifier is fitted after the thermostat). N.B. When this bit of plastic/nylon is removed it improves front to back visibility along the flute.
2. The clamps on the multi bend pipe have 14mm jaws while the clamp on the pipe from the thermostat has a 17mm jaw. When corroded/crusty it easy to get the parts mixed up by visual inspection. Can be annoying when re-assembling and you have used the wrong clamp.
Cheers
Bob
P.S. If by "delivery pipe" you mean the distribution pipe inside the cylinder head, a) you are a braver man than me and b} heed 'Long_Keeler's #16
 
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Sorry, I was confused and dont have a riser. Had not noticed. Did wonder why people called it a riser.It is an elbow.
Make sure then that the water passages in that elbow are unblocked so that you can get a good unobstructed water flow from both inlets through into the exhaust gas .
 
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