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rebuild a motor or take the five old motors i have to make a good one?

  • rebuild the motor out of the part car with 62,000 miles

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  • rebuild the motor in my opel with 132.000 miles

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  • take the five motors i have to make one or two good motors

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i'm new to the world of opel GTs, need help

2048 Views 17 Replies 8 Participants Last post by  greensmurf20
it all started in october, i seen a 70 Opel GT beside somebodys barn and stopped to see if i could buy it for my dad( he used to have one as a young kid and talks about it all the time). I bought the car with two part cars and many many other parts. i hid them at my mothers house until christmas came and then gave them to him, we started workin on it and he gave it to me for my first car. i am unsure of what to do about the motor though:confused: the car runs and drives but it only has 70 lbs of compression at the most and i pulled a motor out of a part car only to find a rod had snapped(weird no dents in the pan and the block is fine) i still have 3 more motors i am getting this weekend and i am unsure if i should rebuild the one in the car or if i should try to take the five motors and attempt to make a good runner. any input would be appreciated very much.
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well the thing is when con rods snap they may bend the crankshaft slightly (which is cast iron and it doesnt bend much they break) but it only need to be off a few thousandths of an inch for them to turn into a problem. but if you can get a new con rod, rod bearings a few new pistons and all new piston rings and a valve job. and that should do it.
Well, you can take all the motors apart, making sure to keep the various parts with each motor and run each one to a machine shop and get them to "eyeball" the various pieces and see which ones can be combined to make one good motor. You'll still need to go through the process of cleaning, machining, new parts (pistons, bearings, gaskets, etc) It's really the only way to be sure of the motor when re-assembled. Any way you look at it, a motor will have to be totally re-built to make it a reliable one.
that sounds like the way i want to go with all the new internal parts. is there somewhere to get parts cheaper than to go through Opelgtsource.com? whenever i find parts they are always cheaper than opelgtsource but its so much harder to find the parts.
jordan said:
well the thing is when con rods snap they may bend the crankshaft slightly (which is cast iron and it doesnt bend much they break)
The Opel CIH engine has a forged crank.

what is a cih motor? what is the difference between a cast and forged crank?
looking for cheaper parts? Take a look at ebay "opel GT". A lot of the sellers have many parts available other than the item up for auction. Tell them what you are looking for. I have got a lot of good parts there.
Good luck with your Opel!*
greensmurf20 said:
what is a cih motor? what is the difference between a cast and forged crank?
CIH = Cam In Head - this is what our Opels have for an engine. The cam is located in the head and the lifters are directly connected to the rockers.
ok. i've been around v-8 chevy's all my life and when we took the valve cover off to adjuste the valves that was the first thing i noticed, no push rods because the cam was so close to the rockers. i am tearing a 1.9 apart tomarrow because i am on spring break so i have no school. it has a broken crank or rod because the back piston does not move but the motor turns nice and free. maybe i will learn a little more about them and hopefully its rebuildable.
I agree,
Take the motor that looks like the best one and drop it in, and drive the car while you are rebuilding another one of your motors.
Thats what I did with my Yellow GT. Also it doesnt really matter what condition the motor you are rebuilding is in because almost everything will need to be rebuilt or cleaned anyway. The motor that I rebuilt was really dirty and rusty, but once they acid dipped it it looked brand new.

yeah i'm finally gettin the other three motors tomarrow afternoon. i talked with my dad and we're just goin to see if any of them have decent compression. the guy said he has a webber carb with all the extra parts i am getting tomarrow. i cant be sure though. i did have some parts in the car when i got it and there is a air breather section that where the end goes over the carb is not shaped like a ovel so i assume thats part of the webber conversion kit?
does anybody know where i can get parts besides the opel gt source, and one thats actually written in english?
Cheaper parts:
As I said earlier...check ebay "opel Gt"! Some of those sellers have a lot more than what is currently up for auction! They are quick to let you know it too. I've had really good luck with parts from there and got some a lot cheaper than expected!
the only problem with ebay is most people do not leave an email address and i'm not an ebay member. i tried to become a ebay member once so i could contact people but they need a credit card number and my dad wont give it out online. so for me its nearly impossable to contact ebay members with parts.
I find cheaper parts at Autozone , Advance Auto Parts (Partsamerica online but the stores will order for you too), and PEPBoys. Not everything mind you, and sometimes prices aren't much less than OGTS, but you should check it out. FelPro gaskets, various seals, water pumps, fuel pumps, brakes, etc. can all be found without much difficulty. If you've got a local foreign car parts store they can probably help too. It's amazing how available parts are for Opels!

I still end up buying plenty from OGTS. They not only sell good quality parts and deliver quick, they also provide much helpful advice when asked. Well worth a couple extra bucks.

Be sure to buy a factory service manual right away if you don't already have one. You can do an internet search and find a number of places that sell automotive literature that will gladly sell you one. Much quicker and easier than playing the bidding game on Ebay. Shop around a little for price/shipping costs though. These books are still quite plentiful, so don't get gouged.
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i got the rest of my parts today and i am kinda P****d off. he didnt have half the stuff he told me that he had.i was expecting 3 complete sets of drive train from the fan to rear end, one full set of perfect glass, a webber carb, and other miscelanious items. all i got was 2 motors and transmissions(one motor part was dissasembled) one rear end, and the full good set of glass. oh well both motors tun over and carry somne kind of compression so i should be able to have a decent running GT. one motor has 150-160 pounds of compression but one cylander only has 60, i'm hopin its a stuck valve or something along that line. so now i have two part cars full of parts and even more, if anybody needs anything email me and i'll be happy to sell at reasonable prices. i would also like to thank everybody for their input and advice, it was much appreciated and tought me some things i never knew about the GTs.
DO NOT have to have a credit card on file to be an ebay member. Just click on contact seller(which is shown on each and every auction item) to communicate with the seller. It's a direct link to his email.
I buy all of the time and I do not have a card on file....I am not that trusting either. I refuse to use pay pal-which is paying with a card. I send money orders for everything as payment. Most sellers do not care as long as the $ is right in the mail.
All you need to be an ebay member is a user id and a password..sign up. It's easy!
when i tried to sign up to be a member it said something about having a free internet so a credit card number was needed.....i dont know. since i'm not a member i just assumed that i couldnt contact them unless they left a email...................i'll try what you said. thanks
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