Thanks guys for your advice and I will leave the engine in its original form. On flat country it has been able to sit on 110 km/hr ( confirmed with gps ) - it just doesn’t like hills and neither did my previous 203. Thanks for all the info on what was done to the engine to return it to service Russell as well as all the other info - much appreciated. Oil leaks both in the gearbox and a lesser extent in the engine are a bit of an annoyance. I know the speedo drive o-ring is one area and I can only manage to withdraw the drive housing about half way before it jambs. Twisting the assy won’t free it- maybe trying removal after a drive might help. There is a leak at the back of the motor and replacing the rocker cover gasket and the oil delivery copper washers have not eliminated the leak - perhaps the head gasket maybe. There is also a weep at the front of the motor around the timing cover which is a common area for leaks.The car had new genuine pistons and liners. The white metal bearings weren't touched and will need doing. The performance was up to 203 standards and it pulled well. It had a heli col done on a plug thread before it was sold. It was restored on the principle of leave well enough alone so the wiper motor was tired but not touched and starter motor/generator not touched. That diff always had more play than I liked. The distributor gave problems. If the motor was pulled down and all put back the way it should be the car will have a satisfactory performance for a 203. The body was really quite good and the paintwork by Carlin & Gazzard of Mt Gambier (taken on as a project) still seems good from photos. It's an early 203 with a solid provenance, that is where it's value lies and if it's modified it quickly loses it.
Some of the larger capacity motors have been disappointing.
When dealing with the leak at the back of the head don't rule out a pipe leak. When I put the head back on after the heli coil I was presented with a head that had not been skimmed and was still coated with the remains of gasket cement that had gone hard. I cleaned it as best I could but wasn't happy with it. It never came back for re-tightening so I'm not that surprised the gasket later went. The car didn't have a temp gauge but I suspected it was running too hot.Thanks guys for your advice and I will leave the engine in its original form. On flat country it has been able to sit on 110 km/hr ( confirmed with gps ) - it just doesn’t like hills and neither did my previous 203. Thanks for all the info on what was done to the engine to return it to service Russell as well as all the other info - much appreciated. Oil leaks both in the gearbox and a lesser extent in the engine are a bit of an annoyance. I know the speedo drive o-ring is one area and I can only manage to withdraw the drive housing about half way before it jambs. Twisting the assy won’t free it- maybe trying removal after a drive might help. There is a leak at the back of the motor and replacing the rocker cover gasket and the oil delivery copper washers have not eliminated the leak - perhaps the head gasket maybe. There is also a weep at the front of the motor around the timing cover which is a common area for leaks.
Wondering if this is possible using the 203 original block with enlarging the diameter to accomodate the bigger liners and other mods such as camshaft profile etc.
wilko
Usually a 203 block is used, this because the distance between the top of the block and the liner seal are is longer in a 403. You can make up spacer rings to fit on the liners in order to use a 403 block, which looks to be stronger, so worth doing this.404 liners can be fitted to 403 blocks. The block needs to be bored to suit. It is a close fit between the liners.
Some say too close.
However I've built a few engines which have lasted and run successfully.
Not as close as the 2 litre but that probably is too close given the liner seal problems these engines have! XU FWD engines also very close but these have an improved liner seal setup.404 liners can be fitted to 403 blocks. The block needs to be bored to suit. It is a close fit between the liners.
Some say too close.
However I've built a few engines which have lasted and run successfully.
IIRC we fitted o rings to the liners.Not as close as the 2 litre but that probably is too close given the liner seal problems these engines have! XU FWD engines also very close but these have an improved liner seal setup.
Good grief, Carlin and Gazzard!! Are they still going? That's a name from the past.The car had new genuine pistons and liners. The white metal bearings weren't touched and will need doing. The performance was up to 203 standards and it pulled well. It had a heli col done on a plug thread before it was sold. It was restored on the principle of leave well enough alone so the wiper motor was tired but not touched and starter motor/generator not touched. That diff always had more play than I liked. The distributor gave problems. If the motor was pulled down and all put back the way it should be the car will have a satisfactory performance for a 203. The body was really quite good and the paintwork by Carlin & Gazzard of Mt Gambier (taken on as a project) still seems good from photos. It's an early 203 with a solid provenance, that is where it's value lies and if it's modified it quickly loses it.
Some of the larger capacity motors have been disappointing.
Bore spacing is OK its the thickness of the lower part of the liner that is the risk. The approach I and others have taken over the years is to machine out 203 blocks to suit 404 sleeves giving you 1618cc. 203 blocks have a little more material to work with than a 403 block on the bottom sleeve mount area.Can the 403 or 203 liners be bored out internally, giving the capacity increase without the effect on bore spacing, seal etc.?
I have 404 motor currently under renovation which has been taken out to 1.8 by overboring liners. Wall thickness rather reduced, which may be a problem but it has a history of having held together under trying circumstances.
Andrew