ford 1703cc engine

[bigminiandy]

I've finally decided to bite the bullet and replace the block on shameless lady. I think there is a crack some where and the previous two owners have had no luck with the engine either!!!

I bought a Consul mk2 Engine to replace the existing which is a Zephyr 4 engine. The original specifications for the two engines says that the zephyr is the more powerful of the two engine. I know this is part down to the head being a different compression and valve size. My question is does anybody know are the two different in any other way, such as cam profile?

cheers

[Mirak]

The Zephyr 4 was basically the Mk3 Consul. The name Consul was dropped from the Mk3 range.

The Mk2 Consul (204E) engine has a slightly lower compression ratio than the Mk 3. Hence the slightly higher power output of the Mk 3. I have a feeling that the Mk3 has a different start motor layout. Pinion/Flywheel ring gear ratio is lower to overcome the higher compression. I think the Bell housing layouts are different between the Mk 2 ad Mk 3 engines because of this.

from the Haynes Manual:

Mk 2 engine was 7.8:1 compression ratio and produced a nominal 59HP net
Mk 3 engine was 8.3:1 - " " - 68HP net


I don't think from memory there was any special cam magic except on the Raymond Mayes conversions, but these are fairly easy to sort out later. I don't think there was an increase in the valve size (without dredging through the manual). the standard head is not that well ported. The Raymond Mayes conversion had much better porting and larger inlet valves

Various Carburettor options are available but don't do much for a boat. Lot's of large carbs just improve the 0-40 mph time of a car and increase the fuel consumption

My Simmonds engine is a Mk2, with a Weber ICH34 carb conversion. This has a solenoid on the idle jet which means that the fuel is shut off as soon as the ignition is turned off. and there is very little fuel vaporization. Engine starts on the key and stops when turned off.

My Dowty Turbocraft has Mk 3 2.5 litre 6 cylinder Zephyr engine and there was a similar modification series, higher compression Mk 3. The Dowty engine has an ancient solex carb which is well past its sell by date and due to be replaced by a Weber conversion when I get a spare couple of hundred quid.

Incidentally, I have a few 1703 spares if you are interested. Crank; cylinder heads; and stuff - PM for a list if needed.


Cheers,
S

[bigminiandy]

cheers for that - very helpful

I should be alright fitting the zephyr head to the consul block then i'd have thought, if i wanted the extra power. Having said that i'll be happy so long as the engines reliable. Once the engines out i'll have to count the number of teeth on the ring gear.

[Mirak]

Should be OK presuming the combustion chamber is in the head. I don't think they started putting the chambers in the piston tops until the Kent Crossflow came along. I've never had the head off either of my beasts (yet).

Interestingly, the 6 cylinder mark 3 head sticks out further at the front compared with the Mark 2. not sure if its the cylinder head itself or the position of the engine mounts. I have a retro fitted hole in the front of the engine box, to allow the thermostat housing some room.

[bigminiandy]

I've had the head off both the engines. The consul more than once as i originally thought it was a blown head gasket that was causing problems. The pistons are flat top and having the heads next to each other on the bench there looks no difference in physical size.

I need new Rings, mains, and big ends but am stuggling to find any. Any suggestions on a supplier?

[puddleduck]

Hi Andy, this guy was always good for gaskets and stuff, may well have rings and shells.

Golden Days Motor Service 01603 881 155 01603 881 095
Dereham Road
Easton
Norfolk
NR9 5EJ

otherwise take a look at the MkII & MkIII Zephyr and Zodiac club

all best

Chris

[bigminiandy]

I tried the mk11 and mk111 club as you suggested at the River Soar but there forums gone down and the chairman isn't up on that kind off thing but promised to ask around for me.

I will try Golden days on Monday and see how i get.

[bigminiandy]

Finally managed to track down all the spares I needed. Found a very helpful chap at a place called newford spares.

[puddleduck]

Andy,

forgot to tell you, I made the aft deck beam removeable so that the engine and gearbox can be lifted out in one piece. Remove the chrome handrail that goes around the aft cockpit, then take a look under the beam. Remove the two or four bolts (can't remember precisely) and the center section with lift out. You'll notice two vertical struts either side of the opening to retain sructural strength of the beam.

cheers!