Getting to know your way around a Seven

[SteveP]

So, I've finally taken the plunge after many years of wanting a Seven and got myself a '89 Supersprint with a slightly hotter engine courtesy of Steve Parker Racing.

 

Suffice to say it is fantastic. Well worth the wait. Although found out today that the engine is capable of much, much more but is currently hampered by an over zealous rev limiter set at 5,800rpm.

 

I hoping now to be able to do some of my own maintenance, like replacing basic parts, seals that are worn, refinishing the dials, etc just to spruce it up a touch and generally understanding what's what.

 

I'm struggling to find a decent text that can describe how to take the things apart and more importantly put them back together again! I have the Haynes book on the xflow engine and that's good. I've asked Caterham about a build manual but being so old, it's no longer produced and from what I can gather an owner's manual (if you can find one) isn't going to help a lot.

 

BOL.com keep leading me into a false sense of security about sending me Tony Weale's book and then letting me down at the last minute.

 

Is there anything else out there I'm not aware of?

 

And if you's indulge me a little longer, answers to a couple of quick (naive) techie questions:

 

Cooling: how do I know if I have a header tank? I have a bottle below the level of what I presume is the thermostat housing on the block, but this bottle contains no fluid (should it) and doesn't seem to have any means of real access - is this just an expansion bottle? If yes, the pressure cap on the housing has 'DO NOT REMOVE' stamped on it - if this is true, how do I ever top up / check the coolant level?

 

Gearbox: 5 spd, straight cut, Quaife item (I think Sierra based) - where would I find the cap to allow the gearbox oil to be topped up?

 

Apologies if this is basic to the point of annoying but I need all the help I can get and this forum is an absolute godsend!

 

Thanks

Steve P

 

[Dave H]

Steve,

 

Welcome to the wonerful world of Sevens.

 

The book you want is the Tony Wheale book Seven Maintenance and Repair.

The build manual should prove useful - even though it doesn't cover the xflow - I can get that chapter photo copied from mine if you want it.

 

The bottle below the thermostat housing as an overflow bottle, and rarely has anything in it. To fill up you need to remove the pressure cap on the top of the thermostat housing. It obviously came from another Ford vehicle where it shouldn't be removed.

If the gearbox is the standard unit upgraded (rather than a complete Quaiffe unit) the oil fill is on the passenger side just at the back of the bell housing. It has a square hole which takes a socket drive. Fill it until the oil starts to flow out the hole. To drain it either remove the engine and gerbox, or go out for a drive to warm the gearbox up, then syphon the oil out.

I think the Quaiffe units usually have a filler in the top of the box, just visible in the transmission tunnel.

 

Dave H

[Dave H]

bum.gif!!! double posting

 

Edited by - Dave H on 30 Aug 2001 15:50:22

[R2D2]

If you struggle to find Tony Wheale's book you could try Richard Spelberg at:

http://www.lotus-books.com/

 

The standard set up on the crossflow installed by Caterham is relatively straightforward. The Thermostat housing that is used (Fiesta I think) should be fitted with a pressure cap with a double seal. The upper seal fits into the top of the pressure cap and allows the complete water circuit to be pressurised. The second seal is just above the thermostat and is pressure regulated by the spring in the thermostat. You will notice that the overflow for the system is between these two seals.

 

If you also check your pressure cap it should have a vacuum valve in the lower seal.

If you look at the lower seal of the pressure cap you will see a slightly domed brass washer. If you pull this gently it should open about 6mm. (If you don't have this arrangement you have a non-standard cap)

 

The theory is quite simple as the engine heats the water expands. Once the pressure exceeds the pressure cap rating water is expelled into the expansion tank (you have described as a header). The upper seal prevents water loss.

 

The expansion tank need to be part filled with coolant and the overflow tube needs to be below this water level with the engine cold and the bloack etc. full of water.

 

Any water expelled by expansion is collected in the tank. When you stop the engine cooling occurs and this will create a negative pressure in the cooling circuit. The vacuum valve in the pressure cap then opens and draws water back into the block.

 

I would check the following:

 

1. You have the correct pressure cap ( Round, no ears marked Motorcraft M100) with a double seal and a vacuum valve.

 

2. You have coolant in the expansion bottle and the overfolw pipe below the coolant.

 

It could also be that someone has fitted a "fully" pressurised system in which case the expansion bottle should be fitted with a pressure cap and always contain water. It seems unlikely that you have this system.

 

Hope this helps.

 

[bstark]

Is this the same book as:

 

Lotus Seven: Preparation, Restoration and Maintenance, by Anthony Wheale, hardback, ISBN 185532153X

 

which is the only one I can find? If not, does anyone know if this book would also cover a live axle xflow, or can anyone recommend the book?

 

I'd like to do more work on the car myself but am fearful of causing damage by jacking in the wrong place etc.

[SteveP]

Firstly, thanks for the replies. Gradually things are becoming clearer.

 

bstark - as far as I'm aware you are taking about the same book, although believe that the surname is spelt Weale. Haven't tried www.lotus-books.com yet, but have talked to another supplier (wwww.millhousebooks.com) who told me that the book is currently under consideration for a reprint, but as to when, he didn't know.

 

bol.com have led me up the garden path yet again for this book - they are not recommended to anyone else trying to find it! Ignore what it says on their web site, apparently it isn't very accurate and not updated very often. Hmm, find that interesting for a so-called web supplier...

 

Steve P

[R2D2]

Richard does have the book in stock. It was only re-printed about 12/18 months ago and should be available.

[bstark]

Thanks Steve,

 

I got the information from Foyle's (World's biggest bookstore etc.) who reckon they can get it for me in 7 to 10 days for £22.50 + £2.95 p&p

 

If you want to contact them try sales@wgfoyle.co.uk

 

[SteveP]

Have tried www.lotus-books.com

Received reply today saying that Tony Weale's book is out of stock and print - the search continues!

Trying Foyles next.

[aideen]

According to http://www.chaters.co.uk/

"Reprint Under Consideration"

 

Is a rev limit of 5,800rpm over zealous for a x-flow?

 

Aideen

 

[SteveP]

I was taking the advice from Steve Parker who originally constructed the engine. He told me that 7 - 7.5k is more like it (peak power isn't produced until 6.5k apparently).

 

But, having checked the history, it looks like the original pistons (described as American pistons - does anyone know what these are?) have been replaced but I don't know what for, so I'm now a little cautious to push the engine too hard.

 

I've also disconnected the rev limiter altogether since I couldn't get it to adjust any higher.

 

If anyone has any info on the setting and testing (for which there is a separate spade terminal) of a Micro Dynamics RL3 rev limiter, it would be most helpful since I'd really like to put it back on!

 

What rev limit do other xflow owners have their cars set to?

 

Steve P

 

 

[Jam Mad]

mine's at 6000. more than enough to have fun with, while leaving me with a nice warm fuzzy safe feeling.

 

as an aside... my first non starter the other week was diagnosed as a malfunctioned limiter.... that had somehow reset itself to 0 over night !!!

 

worth remembering as an option if you ever find the engine fires, goes fine for a second or so, and then dies. again and again. and everything else looks fine.

 

have fun...

[bstark]

I was advised to use 6000rpm as a normal limit for my Steve Parker 1700 xflow - but was told 6500rpm would be safe occasionally if I needed the revs on a track day cool.gif

 

Having said that, I lose power at about 5200rpm (shame, as it flies up to that) as the pesky garage who fitted the engine before I bought it used the same carbs from the old 1600 xflow previously fitted - complete with the same jets. Rolling road tune at the weekend to sort that one out...