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$5,000 Engine Rebuild?

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Obtong

Obtong

Jedi Hopeful
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Dear All,

My 74 MGB was still having problems going up steep hills. I did the following to improve things:
* Balanced carbs and readjusted idle
* Installed new air filters
* New plugs and points
* New (Sports coil)
* Adjusted timing

Despite all my efforts the MGB’s uphill performance still didn’t improve; I kept stalling on steep inclines (and had to roll backwards into driveways).

I decided to take the car in to my local MGB shop. I was told that the compression on two cylinders was low (115-120 psi) and that the engine would probably need a rebuild. I was quoted $5,000! I was shocked

The mechanic told me all the things that he’d do: new valves and cam, grind something (I forget what it was) and rebuild the carbs, etc. An impressive list of “to do’s”, but there is no way I can afford that kind of money to go up hills! I could probably buy a really nice MGB for that amount of money.

So, what do I do? Do I sell my MGB to someone who knows how to do this, or is there a less expensive approach? Remember, I am a beginner so I really don’t feel comfortable taking the entire engine apart. BTW, the MGB doesn’t lose that much oil, so perhaps I can get away with just replacing the cam?

Any help will be really appreciated!

Thanks,
Obtong

P.S. I cannot get to work in my MGB because I have a couple of hills to go up!
 
Just for a price comparison, I know you can get a rebuilt 1950cc engine painted, shrink wrapped, and ready to install for about $2600, if you chose to keep your existing engine (IE: don't return yours for the core value) then the price is $2900, then you need to find someone to remove the old one and install the new.
 
5K is, in my opinion, a bit pricey for a rebuild. I know of one shop that charges in this range, and is darn well worth it, but I could never afford it. You can pick up rebuilt long blocks from the usual suspects for about $2500, have your carbs rebuilt, and be ready to go for about $3000, still pricey for me. I bought a car this week mainly because it has a great engine and many other parts I need for my rebuild, and paid less than a grand. I only paid that much because it is driveable and I intend to do so this summer while I work on my other car. I don't want to spend the summer without a convertible
 
or if you want to do nothing but drive it you could work out a trade with Chris Roop who is also in the north west. He currently has several really nice cars for sale. Roop's MG
 
5K too much for a rebuilt engine? Maybe, maybe not. Depends on what you do and who you pay to do it. I would not pull an engine out and put it back in and get it running right for less than $500. When you boil the block, replace freeze plugs and oil gallery plugs, rebore and deck the block, regrind the crank, replace the cam, replace all pistons, cam followers, maybe the rockers, rod and main bolts, all bearings, valves, guides and seats, oil pump, water pump, rad hoses, oil lines, clutch.....and the list goes on and on, it really adds up. FWIW, I have one engine that I have 5k in, not including my own labor, but it is a 1950 with lots of machine shop work, Lotus pistons, new rods, etc.
 
Thats a lot of money for a B rebuild. We used to charge around 3k, but that was new pistons too. I doubt if 120psi in two of the cylinders is what your problem is either, but that depends on what the other 2 holes read. If you want to take the engine thing a little deeper, find out what shops have a "differential pressure tester",(all of them should) sounds fancy, but it basically a modified compression gague, it uses shop air to pressurize each cylinder at tdc and twin gagues, one for psi in to engine, the other what it holds. Depending on where the tech sees/hears the escaping air is what is lowering compression. exhaust-exhaust valve, carbs-intake valve, radiator-head gasket, dipstick or out of block, rings. I'm surprized the shop didn't do that anyway, I do as a matter of corse on a low compression cylinder. Unless you are burning/using oil other than the territory marking habits of your car, its probably a burnt valve anyway.

But I still don't think that compression will give you the problems you have. You'll have a miss, a rough idle, low power-sure, but you'd be complaining about it more than just on a steep hill. I'd make sure the fuel system was in good shape. 3psi to carbs, 5 max. or the jets can't stop the flow into the engine, and it floods. Check the delivery rate, jack the front up and check again, maybe there is some junk that drifts back to the tank outlet going uphill. If it stalls, and won't restart while still facing uphill, but will when you roll back and change direction......well, compression is certainly not the problem.

Keep in mind, nobody can fix it over the phone,(or www) maybe the engine is toast, maybe you need turn signal fluid. I'm just saying before I threw in the towel or spent the kids college fund, I'd want to know exactly what was wrong.
 
Your DP tester sounds like a cylinder bleed down checker to me. I made my own with a single gauge and an air line. I pressure up a cylinder and watch how long it takes for the pressure to leak down. At the same time I listen for air flowing back through the carb, the crankcase and the exhaust.
 
Had a Fiat X1/9 years ago, bought used and cheap and it wouldn't go up hills either. Fixed all the usual subjects, ignition, carburation (adjust not rebuilt) adj valves etc, solved the problem under fifty bucks and never had to open the engine up. Don't panic or spend a lot of money unnecessarily. Get a second opinion, heck, even a third. Find an honest mechanic. As mentioned above, compression of 120/130 is no big deal. Might effect smoothness a little but not hill climbing ability. (Add a dist cap and wires to your list, can't hurt) Bob

[ 04-16-2003: Message edited by: Bob Claffie ]</p>
 
Obtong,

I agree with the above...and it sounds like a fuel delivery problem to me. As an old hill climber, I can recall the old carborated Jeeps that used to stall on the steepest parts of the power lines from starvation when the carb floats would run dry because the mechanical pumps couldn't keep up enough pressure unless you kept the RPMs up. If your fuel system has even a slight problem, 3PSI is not gonna overcome it easily. Higher RPMs are not gonna help with an electric fuel pump. If you stop immediately when the car stalls and check the fuel system on the spot, it should be evident where it is getting hung up on the delivery side. If it is getting to the carbs fine, then the place to start is with the carbs. A manual choke would let you add choke before the stall...this is temorary, but would prove to you that it is (or isn't) a carboration problem.

Good luck and check back with us before you rebuild!

Bruce
 
Dang, for $5K I'd think you'd be able to do the Rover-Motor swap.

Hills? What hills?
grin.gif
 
DON'T TRY IT YOURSELF unless you are very mechanically inclined and have some prior knowledge of what goes on inside an engine. Clearances in the thousandths, extreme cleanliness, attention to detail, following directions are all VERY necessary. You wouldn't give a dentist a scapel and ask him to do a heart bypass would you? He is a Doctor, right, just not the correct kind. Start practicing on less essential things like wheel bearings and exhaust systems and work your way up to a valve job. MAYBE then you will have the smarts (and confidence) to tackle a motor. Bob
 
Sorry to turn this in my direction but what kind of maintenance would a totally restored MGB still require? I'm really interested in owning one but I have very little real mechanical know-how. I could possibly do some very basic maintenance myself but otherwise I would have to pay a professional or possibly a fellow club member to work on it though I'm not rich. Am I in over my head? Should I leave you all alone and just get a good, reliable, boring car?
 
Thanks for all the input folks. You've certainly given me a lot to think about and places to check out before I take that final plunge!

DIY Rebuild: Possibly, but I'd have to give it a lot of thought first. To date, the most mechanical thing I've done is change the plugs/points/rotors/cap! The DIY rebuild looks like a HUGE step that at this point I don’t think I have the skill (courage?) to undertake! Thanks for the encouragement and advice though.

Fuel Pump: I was assured that the fuel pump is OK. Giving more choke on the hills doesn't help much. Also, after stalling I can usually start. It’s once I put the car into gear that I cannot get enough power to move even a foot before the car stalls again. Reverse (with gravity helping of course) is OK.

Other: I will give a couple of places a call (thanks Bill) to see what they have to say. Also, a friend of a friend who is a mechanic (I think) is going to take a look at my MG next week. It’ll be interesting to see what he has to say. I will keep you poted…

Thanks for all your replies,
Obtong
 
Reply to Laex:

Totaly restored kind of implies that it would be in good working order. If that is the case you would probably just need to do routine maintenance for the most part. I know very little about car maintenance/repair, but have learned A LOT through THIS FORUM, and by reading the Haines manual and Moss catalogue. I have found Lindsay Porter’s Step-By-Step Service Guide for MGBs to be very helpful.

I’ve actually saved money by having this MG. I now know something about how cars work and what the symptoms of some basic problems are. This is useful stuff to know when you have to bring your other (reliable?) car in for service/repair.

I’d say go ahead, you’ll have lots of fun and will learn lots. Once you own an MGB there’s simply no turning back!

Obtong.
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by Obtong:
Reply to Laex:

Totaly restored kind of implies that it would be in good working order. <snip><hr></blockquote>

Obtong, FYI, if you want to reply to a particular person or post, just click the Quote Marks " " in that person's post header and then you can quote all or part of that person's post. FOr example, I am quoting part of what you said and it tells that I'm quoting you.

Basil

[ 04-17-2003: Message edited by: Basil ]</p>
 
Obtong:
Go to the parts store, buy a compression tester, doesn,t have to be expensive. Check your own comp., if within 25% of each other look elsewhere, like exhaust. As it gets warmer and is clogged or bent will cause same problem, also check fuel flow, clogged filter will do same.
Larry
 
I don't mean to confuse but I've changed names oh and sorry for posting on this thread, just wasn't sure to start a new one. Obtong, I appreciate the advice. I was thinking of either a Spitfire 1500 or more likely a rubber bumper MGB. Though I wouldn't say I'm that mechanical or even handy, I do at least I have a positive attitude
smile.gif
. Maybe I'm just more like a miata driver
frown.gif
...I do look foward to being part of this forum, it really is helpful!

[ 04-17-2003: Message edited by: Lakes ]

[ 04-18-2003: Message edited by: Lakes ]</p>
 
As someone who successfully rebuilt a mid 90's Ford engine (with all the emission controls and computers) And as someone who had little mechanical experience to begin with, I'd suggest that you look into rebuilding it yourself. $5,000 sounds like an outrageous amount to me. I'd assume around $3,500 of that is going to be labor.

With a couple of manuals, access to a local machine shop that can do some of the precision work, and a week or two of down time, I can't imagine a do it yourself rebuild costing more than $1,700. It also gives you a chance to notice and correct other problems before they occur. (That's something a Garage may not worry about when they're just working on the engine.)

Do it yourself. It's cheap, it's educational, and it's very rewarding. YOU CAN DO IT!
yesnod.gif
 
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