Thread: 3.5 rebuild

I recently had the same dilema with my Stage 1
After much thought and deliberation I bought a fully rebuilt 9.35:1 comp ratio from Rangie Spares it only cost me $2500 for a long motor with cam and lifters. These engines were rebuilt when they had the engine shop and were done properly (hot pressure test etc)
I have rebuilt a number of motors but didnt have the facilities to do the job properly the end result after 10000 kms is that I am very happy with the motor I bought.
For the record the higher compression ratio is sooo much better on LPG.

They are not a complicated motor so you shouldnt have a problem, check out the bore on the spare engine as it may only need a hone and new rings/bearings and of course the cam/chain/lfters. I have pulled both the 3.5's in the 2 rangies i had (sold one last year, other i still have after 13 years) and the bores were still good and the cross hatching of the hone could still be seen. I have bought some parts off uk ebay and had them landed about 30% cheaper than sourcing local. 3.5 shorts are a tough little motor. A 2 brl should flow enough for lpg so i would just mill down a stock one .

One thing not to skimp on is the rockers and shafts.
thye will almost certainly be worn out.It is false economy not to replace them.
Regards Philip A

assuming you get the block and the heads machined by professionals theres a lot of worse engines you could choose as a first time rebuild..

Enjoy, take your time with it, Know that youve done it right and If you think you might have got it wrong pull that bit out double check and go again....


Oh Hope your going to run a thread on it.

Hi Dave
Will do.
Perhaps I can run a rebuild story.
Wont be doing anything with the Stage1 till I finish my un-started trailer project!!!!
Best bit is I have already spent $$$ on the Ser3 in the shed,I will be able to scab anything I need of it and sell leftovers!!!
Andrew

oh if your that way inclined the 3.5 doesnt mind a marginally lumpier cam with just a tad more overlap... but that will wear the rest of the valve train a tad more... Dont skimp on those parts.

Originally Posted by LandyAndy

Hi Guys
Is the 3.5 an easy motor for the DIY novice to rebuild????(can use tools/follow a manual)Have a local engine shop that can do any machining needed
The motor in the Stage 1 is cactus,from memory has a spare motor of unknown quality.
Intend running LPG all the time so will be looking for a 4BBL manifold to run a reasonable size carby with a Sprintgas LPG setup.
Any idea what a rebuild on these costs?
The cam is stuffed on this one,will put a decent one in.
Any other tips that these motors need doing whilst in bits???
Andrew

G`day Andrew

They`re no different to any engine of the same style/era , all the same things apply .

The condition of the engine dictates if it`s worth/viable to reco and this can only be know after dismantling it .

Things like if the piston skirts still have the grooves around there circumference they are good but if the skirts are polished/smooth they have done alot of work or sucked alot of dust .

The deck of the block if in good condition will show no obvious height difference between itself and the liners it should all look like the same surface other than the different colours of the liners but that`s not to say that a block with liners that have dropped will have problems just means at some stage it may have been overheated or the clearances rings/bore etc , may have been not been right initially .

Depending on which 3.5 you have there are 2 different ring thicknesses , early use thicker that latter .

For LPG only you will require plain cast rings etc or be able to run it in with petrol for the first few thousand Ks .

Rover use chrome and they will seat but it could take 10s of thousands of Ks , could be less and may be never .


They can develop loose liners after being rebored so it`s can be an expensive road though there is an easy fix but requires new gasket because of head removal .

I`d suggest you price the parts needed first then decide is the cost and time reasonable .

Also price Rover and aftermarket , you will probably find there is a huge variation and with who is selling the same bits also .


If you have a fairly good engine that after measuring will take rings and bearings etc you`ll have no problems and it won`t be too expensive if you can shop right . ( things like a Rover cam at $280/300 and a cam from a place the grind their own at least $100 less ) but if you need bore work and new pistons etc it may not be viable to do it yourself .

I`d also you get prices for getting it reco by an engine shop , they will most liklely use aftermarket and may have the capacity to by/sell parts cheaper the you are able to buy for .

I know of people that have done as your considering , they assembled themselves got the machining done by an engine shop and for all their effort a bit more than $3000 was the worst because there`s a point when you can`t stop because too much has already been spent .

When the problem occured with our 3.5 a got a new 4.0ltr crated block which was less than $2000 but that was a few yrs back now .

I have four 3.5s in the shed 3 apart .

One will take rings/bearing etc .

One will get same aswell as one liner and piston .

One will get scrapped .

Cheers