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Fridge

Restoring a 907 Engine - What to Check and Change?

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Hi,

I'm about to restore a 907 engine and I was wondering what members thought of the main things to check and replace, beyond the usual timing belt, cam tensioner and water pump.

Thanks in advance.

David.

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Is the Engine still in the car? Has the engine given you any problems?

Buddsy


 

"Belief is the enemy of knowing" - Crrow777

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7 hours ago, Fridge said:

Hi,

I'm about to restore a 907 engine and I was wondering what members thought of the main things to check and replace, beyond the usual timing belt, cam tensioner and water pump.

Thanks in advance.

David.

Did you mean restore or tidy up so it ran.... ish...   To restore you strip the lot and change every  worn part ,  you remove every single stud and component back to its bare bones inspect replace, then accurately rebuild to spec , and more..   Anything less is just maintenance... Far to many people say their engines are restored when really just cleaned and serviced...  So the answer to your question on the main things to check and replace,  is the question , do you want to restore it or just tidy it up. !!!!.. 

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Hi thanks for the responses.

Although I was really looking for details of any 907 foibles rather than the general things to check in any 4-pot engine. At this point in time I'm looking to assess the current health of the engine before I take further steps. This may involve turning over, running then partial or full strip down. Depending upon the outcome of the initial investigation.

The engine is currently still sat in the chassis, along with the carbs, exhaust, gearbox etc. However, the body shell has been removed completely. Along with the fuel tanks etc. It should be easy enough to connect up electrics etc. As I am undertaking a complete, nut and bolt restoration of this car.

The engine is an unknown quantity, as the owner had passed away before I obtained the vehicle, and it was not in a state to run. Let alone drive. However, it has had some work completed. Such as some head work it appears, stainless steel exhaust system etc.

Thanks once again for any advice that can be given.

Regards,

David.

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If its a nut and bolt resto then thats what should be done.

Gaskets and parts for an engine rebuild cost approx. £3K Become a FFM and youll get 10% off that which will save you before you start.

 

Buddsy


 

"Belief is the enemy of knowing" - Crrow777

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Thanks Buddsy,

With some work already completed, I may not need to completely strip and replace parts, but I do need to check the current state. Hence my original post.

Regards,

David.

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Normally I would say change the belt and get it running to find out how it runs. But if you got the body off and doing a full resto I would take the engine out and do the lot. Getting the engine out when the car is finished with nice paint and all would make you curse!

 

Buddsy

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"Belief is the enemy of knowing" - Crrow777

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3 minutes ago, Fridge said:

As I am undertaking a complete, nut and bolt restoration of this car.

Well its a no brainer then !!..  Waste of time trying to fire an unknown engine just for the sake of it.. even if it runs it will not tell you the whole story...  If as you say you are doing a complete nut and bolt restoration of this Esprit , then that should include the engine and gearbox, carbs etc etc ,   otherwise it is not as you say complete..  These restorations when done correctly are a costly and time consuming exercise..  anything less is just a DIY tidy up...,  if the job is worth doing, do it right..  Garages are full of well intentioned restorations which eventually end up on E-bay as bits..  You will get valuable help off this forum from privateers that have undertaken what you are suggesting.   You should be budgeting circa £20k for a proper job with most of the drudge work done by yourself..  £3k for the donkey done yourself is about correct.. £6.5k by a proffessional.., 

2 minutes ago, Fridge said:

 

With some work already completed, I may not need to completely strip and replace parts, but I do need to check the current state. Hence my original post.

Regards,

David.

 Even if some work has been done by another, you need to question to what standard.. Always best to do the lot regardless, photo all the way through as history evidence and you will have a treasured piece of history to be proud of  ....

Good luck with your endevores.   

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Thanks Changes,

I've restored plenty of cars previously. Most still in my possession. I was really looking for specifics and advice from folk who will have worked on and restored a 907 engine. I think you've slightly missed the point of my original and subsequent posts.

Regards,

David.

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Hi David

Well in that case you should be aware of the costs and work involved.. However if this is your first Esprit be prepared for a few surprises.   Back to the Engine.. I have twiddled a spanner on the odd one or two and would suggest the best option would be full strip and rebuild , this will eliminate all areas of concern.. Anything less will leave doubts.. As engines go they are very good but do have their little quirks.. When built well will serve well, when just played with can give you all sorts of head aches..  Its pointless restoring the Esprit and not doing the donkey.. The seals and gaskets will leak if not done and the bearings will show ware , particularly #1 main ( top) .  You can not asses the bores and rings without stripping and the cam followers will all need replacing.. You may even find cracks in the odd one or two..  if it has stood a long time you may wish to check the conformity of the valve springs as well.. also the guides..  As you see the list can go on and on..  It really comes down to what you want from the final product,       

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David. The 9** series engines are pretty much the same as most other engines. The only thing I can think is some people say there is a cooling flow issue around cylinder No.4 which means its best to keep your interior heater set to hot, but I think that may be less of an issue on the non turbo cars?

Other than that nothing special to most any engine.

 

Buddsy


 

"Belief is the enemy of knowing" - Crrow777

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8 hours ago, Buddsy said:

David. The 9** series engines are pretty much the same as most other engines. The only thing I can think is some people say there is a cooling flow issue around cylinder No.4 which means its best to keep your interior heater set to hot, but I think that may be less of an issue on the non turbo cars?

Other than that nothing special to most any engine.

 

Buddsy

 Valid point there Scott..   On some engines, mainly the early ones, I have found deposits in the water jacket primarily around #4.  This has dried within the jacket to a crust.  Its make up is like alloy scaling off the block from incorrect or no antifreeze use.. In one case it may have been escalated by excessive use of rad weld.. on final removal of this in the worst case, it had caused the corrosion to eat through the block from the water jacket to the outside..  This is not an area many look at unless changing the liners..   Also on all the pre Zues block and head castings the water ports into the head are very poor quality..  It is standard procedure on all my builds to open these out..  The head cooling is far more efficient when done..  I managed to find a couple of old pics that show before and after..

engine strip 068.JPG

HPIM3885.JPG    

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Also, although there are nice big triangular holes in the head face, there are only little circular ones in the gasket. I took a fretsaw to mine and opened them out to just inside the head port shape. Been working fine for years... Agree about the water inlet from the pump, that will need work too.


Scientists investigate that which already is; Engineers create that which has never been." - Albert Einstein

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Thanks Buddsy, Changes and Molemot. All useful information there. We'll be disassembling the engine over the next 2 weeks and check these out before we decide how to proceed.

I've seen cylinder 4 water jacket problems before on other engines, particularly Rootes 1592cc. Possibly because of being furthest away from the water pump perhaps?

 

Cheers for the photos. First class.

 

Regards,

David.

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