Rover V8, are they too light to use as a boat anchor?

[andyborris]

As you can tell from the title, I'm getting annoyed with this bl**dy Land Rover with a V8 fitted!

Quick recap:

Purchased an overheating Land Rover with a 3.5 V8 conversion for a good price.
Removed heads and had them skimmed, still boiling.
Tried a 2nd pair of heads, nope, no good.
Replaced engine with supposed good 3.9 Serps Interim engine (the one with multi rib belt and distributor), only to find the heads had been skimmed so much, my manifold wouldn't bolt down.
Swapped heads for the first pair, then tried the second pair again. Still very kettle like.

So, bit the bullet and buy a pair of heads from V8 Developments, fit these using studs, taking great care to torque them down. Use O.E. inlet gaskets.
Fit a new cam and lifters at the same time.

Engine sounds great, flies down the road and after 5 mins, will make a great cup of tea!

So, what am I missing?

Every time I've pulled the heads off, the gaskets have looked fine, always used Elring head gaskets, tried both tin and composite. Taken care to line the manifold up and to get it to seal.

Has anyone got a good 200/300 TDI to sell?

Thanks

[colnerov]

What radiator are you using?

[bmw2101]

and also is the rad covered in mud or is it blocked

[andyborris]

It's a new Series 3 brass rad that's very clean and done less than 3 miles! It did have a new Series 3 modern style aluminium rad, that sprung a leak, replaced with the brass one.

Both have the same fan set up, which works very well, takes the temp down by 10C in less than a minute. However the fans didn't activate, don't remember them activating on previous boils either, but that may be because I didn't let the engine run for long enough.

Fan switch is in top hose, the silicone top hose was touchable, the rad just over touching temp. Also tried engine with and without a thermostat. It's got a new Gates on fitted at the moment.

So, bypass the fan switch ad have the fans running all the time to see it that makes a difference?

And a 200/300 TDI is looking better, the MPG gain will make the Landy more usable!

[andyborris]

Should add, lot's of converted Series 3 V8's run the standard rad.

[carat 3.6]

Going to ask an obvious question, but you've checked the water pump is circulating water?

[zeberdee]

Does it have a thermostat fitted & does it work ?

[ChasR]

For me, there are a number of things to ask here:

-Is there evidence of the water circulating around (i.e water pump)

-Is the correct thermostat being used? I doubt it would inhibit things too much, but if you need a bypass foot, to stop non-rad fed coolant from circulating around the engine when warm, this is going to cause issues.

-What gauge setup are you using? Do you know if the sensors are calibrated to work with the gauge? Stag ones now overread and have a different tempearature curve. I quite like the VDO gauges with a VDO sensor for this reason or a Smiths capillary gauge

-Where is your temp sensor located on the engine?

-Have you do a HG test with the fluid in it? (i.e a HG tester)

-You say the rad is new and only 3 miles old? Was it brand new or simply new to you? What core design does it have? Most rads of this age can have different cores, depending on who sold it, which can affect things. I doubt it would affect it here, but you never know.

-Where does the rad fill from? If the rad level is below the engine heads, it will be a pain to bleed potentially. A header tank put into the top hose, to try and get around airlocks?

[andyborris]

Coolant does seem to circulating, can see flow across the top of the rad core and this thermostat hasn't been checked, but it's a brand new Gates one and it's the 3rd (I think) to be fitted. can see a temp drop on the gauge when the thermostat opens.

The rad does seem to be cooling, top is too hot to touch (just), bottom is cooler.

Fitted a new Durite mechanical temp gauge into the standard manifold port, watched it hit the stop past the 120c mark!

Pretty simple plumbing, bottom hose to water pump inlet, top hose from thermostat to rad. Rear manifold outlet to heater and from heater to top hose. This also has a non return valve in it, water can only flow into the top hose.

This was added in case the flow was circulating just around the inlet manifold.

[andyborris]

Rad is brand brand new, it's the old fashioned brass type, just a replacement Series 3 one.

Filler is the highest point.

It's not just the gauge reading, it's the steam from the rad, that gives it away! The gauge probe is position is stock, in the front of the inlet manifold next to the thermostat. The gauge is a few degrees out (reads hot), but that might be down to the elevation here in the Brecon Beacons! Just moved here and, of course when I needed my thermometer probe, couldn't find it!

Haven't done a HG test, but the last few times I did it, was very inconclusive. However, you could see the bubbles in the coolant from (I think) a cracked head, even when the coolant was cold. No bubbles this time.

I'm wondering if the wrong water pump has been fitted, turns the opposite way. The pump looked nearly new when I removed it to change the camshaft.

The only other real difference is the Serps drive belt, it's missing a few pulleys (air con power steering), perhaps my new routing is turning the pump the wrong way? Is that possible?

[igor]

Nov 29, 2023 18:01:26 GMT zeberdee said:

Does it have a thermostat fitted & does it work ?

This. Thermostat jammed shut will cause boiling with the top hose still cold. It did on my Falcon anyway. Not sure of RV8 setup. Prob similar.

[dodgerover]

It's not running massively lean or timed completely wrong?
I think they are generally tough old lumps it would be odd to have 2 duds.

Is water circulating through the heater circuit?

[colnerov]

Nov 29, 2023 19:45:35 GMT andyborris said:

Rad is brand brand new, it's the old fashioned brass type, just a replacement Series 3 one.

Filler is the highest point.

It's not just the gauge reading, it's the steam from the rad, that gives it away! The gauge probe is position is stock, in the front of the inlet manifold next to the thermostat. The gauge is a few degrees out (reads hot), but that might be down to the elevation here in the Brecon Beacons! Just moved here and, of course when I needed my thermometer probe, couldn't find it!

Haven't done a HG test, but the last few times I did it, was very inconclusive. However, you could see the bubbles in the coolant from (I think) a cracked head, even when the coolant was cold. No bubbles this time.

I'm wondering if the wrong water pump has been fitted, turns the opposite way. The pump looked nearly new when I removed it to change the camshaft.

The only other real difference is the Serps drive belt, it's missing a few pulleys (air con power steering), perhaps my new routing is turning the pump the wrong way? Is that possible?

Yes check the belt routing and the water pump are correct for each other. Because as you can see direction is evident.

[kevins]

Does it have a degas vent hose behind the thermostat, usually comes out of a triangular boss screwed to the manifold. I had the same on my TR7V8, gas builds up behind the thermostat and it either doesen't open or does very late after the temp gauge has gone into the red.

[datman]

As an aside, rad switches tend to be in the bottom hose, or bottom of rad because the water coming into the rad is always going to be hot, but having the switch in the bottom will only put the fans on when the rad is not managing to cool (ie when car stationary)
I have 2 Rover V8s at the moment, they are not a great engine, low powered and a tendency to wear out camshafts, I believe the 3.5 is better than the 3.9 in terms of porous block.
Can't really help with your overheating woes.
I also briefly had a v8 powered Series 3 landy. Never went out on the road in it.

A lexus V8 would probably run forever without touching it, but they are getting expensive and quite complicated to install.

[andyborris]

Timing seems pretty close, haven't been able to get it running well or long enough to do more, likewise the fuelling.

Thermostat is opening, top of rad is hot.

Fan switch is in top hose, because of lack of space in and around the bottom hose.

So, I'm thinking one of 4 things:

Heads not sealing.

Water pump not pumping, (but it looked OK when checked).

Fans not working, either not switching on or the installation is poor.

When I first got the Landy, it had a big fan in front of the engine, blew very little air through the rad and looked awful.
So I replaced the big fan with 4 small fans behind the rad, mounted on a flat plate cowl. This is just a flat sheet screwed to the rad, a hole cut for each fan and then a fan, it does reduce the open space behind the rad by about 35%.
However, the fans do take heat out of the engine very quickly, 10 degrees in 60 seconds.

On the latest overheat, I don't know if the fans activated, because the exhaust is too loud and the Landy vibrates even with the engine switched off!

When it warms up bit (-4 today!) I'll check the fans are switching on.

[kevins]

I doubt it's the fans it will barely need a fan in this weather, mine will sit for ages idling before the fan comes in, have you tried it without the thermostat? would allow you to check there is plenty of flow and rule out the stat.

[andyborris]

I have tried it without a thermostat, on both the 3.5 engine with skimmed heads (skimmed to be flat!), the 3.9 with those heads, 3.9 with 3.9 10 bolt heads, 3.9 with 10 bolt heads and head studs.

Haven't tried it with these heads, but it does seem to be flowing. I can see strong flow across the top of the core and the top hose and rad get hot, with the lower part of the rad cooler as you'd expect. In fact just the same as without a thermostat.

My problem is that I've had the same problem across 2 engines and 3 sets of heads, the latest heads being from a very well respected V8 specialist!

So, either I've got no idea how to fit Rover V8 heads (very possible!) even though I've had a lot of practice lately or it's something else that's not in the engine?

[colnerov]

I'm still curious about the water pump, take the top hose off the rad and start the engine, is the water being pumped out of the hose?

[andyborris]

Nov 30, 2023 17:40:49 GMT colnerov said:

I'm still curious about the water pump, take the top hose off the rad and start the engine, is the water being pumped out of the hose?

I have a cunning plan....

Will try this, also doing the same with the manifold to heater hose. Heater hose when cold, (it's also the pump bypass), then when warmed and thermostat open (hopefully) the top hose.

Then wiring a override switch for the fans, which aren't switching on.

Then try it with rad shroud and fans removed, to see if the (possibly) reduced airflow through the rad is the cause.

Although I think at even 30 mph the airflow through the rad and shroud should overcome the restriction of the shroud and fans.

If I have a spare thermostat gasket, I'll try it without the thermostat too. Maybe after I test top hose flow?