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1500 engine issues

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Ohiospider1975 Avatar
Ohiospider1975 Warren Brown
Findlay, OH, USA   USA
I took my newly purchased MGA out for my first drive. Well sort of. The car starts, and commences fine. Engine to transmission interaction fine. But within minutes it is quickly overheat(temp gauge climing from 160 through 190 up above 212++ F). At this point the engine is unable to accelerate the car no matter how much I depress the gas pedal. No power. I have to disengage and play with the clutch to get the engine up to 3500 rpm. Once there, the engine will pull the engaged gearing up above 4500. But if the engine falls down below 2500 rpm, I cannot get it to accelerate. This is in 2nd or 3rd gear. If I take my foot off the gas, then the engine immediately stalls. It will not restart until it cools down (20 minutes). Then the process starts over again. Radiator is full, but the cap has no seal. Fan turning on belt, not loose. Lots of gas smell. When the engine is hot, lots of backfiring and load sputtering (pre-ignition?) Does not occur when starting out with cool engine. The transmission housing by my right leg puts out a lot of heat. I mean a lot...enough to make me sweat. I went on a 50 mile drive. The first 10 were fine. Then the fun began. 2nd 10 fine after a 30 minute wait. The final 20 were a drag. When the car is hot no matter how far a depress the accelerator, I barely get an idle response. Any uphill grade, kills the engine.

Any thoughts?

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TeamEvil Avatar
TeamEvil Thomas C
Kingston, MA, USA   USA
Whoa, is this a joke post?

When the engine overheats you don't WANT to accelerate or rev the engine up to 3,500 hundred rpm or do anything else other than shut it off ! ! ! !

Without a seal in the cap your cooling system is no longer pressurized, and the water will just peculate off and . . . hey, WAIT a minute . . . this IS a joke post isn't it ? ! ? ! ? ! ?

And I fell right into the trap.

Basil Adams Avatar
About 12 miles from Sears Point, CA, USA   USA
Check your timing and vacuum advance. If you have too much advance dialed in, it will overheat. Best of luck. Basil

Basil C. Adams
1956 MGA Coupe (Show Car)
1957 MGA Roadster (Driver)
1958 MGA Coupe (Racecar)
1959 MGA Coupe (unrestored)
1960 MGA Coupe (unrestored)
1960 MGA Roadster (Driver)
MKIII Elva Courier (E1056)
1967 427 Cobra
1972 Alfa Romeo Montreal
A coupla late MGBs
1960 Austin Healy BN7
More Cars than Brains

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Rowdy Avatar
Rowdy Jeremy B
Brisbane, Australia   AUS
1960 MG MGA 1600 "Little Red"
Check your thermostat isnt stuck closed, I had anew thermostat seize closed after approx 1500kms. Coolant boiled every time, but i didnt rev it or drive far, looked for the problem instead.

Hollywood,CA., USA   USA
Gee Warren... as Thomas C put it..... maybe you are joking.... in that case I'll go with it and advise draining the radiator and removing the fan belt. Drive your car uphill into a bad traffic jam. See if there is any change. If there isn't then you'll know it must be the timing. If you've gone to 12 volt thatn put the battery on the other side to draw the heat. Put the car uo on jackstands and place a brick on the accelerator pedal. Walk away for one hour... if there are still no changes than it could be the ....I 'm guessing the engine block paint.

mgageoff Avatar
mgageoff Geoff Howard
Ashburn, VA, USA   USA
Since he's probably not kidding, can anyone explain the correlation between engine temperature and clutch function? MC fluid temp?

Geoff Howard
Now Playing on the Blog (8/8/2013): Don't Blow Your Top

HL Miller Avatar
HL Miller Henry Miller
Chair City, NC, USA   USA
In reply to # 1989803 by mgageoff Since he's probably not kidding, can anyone explain the correlation between engine temperature and clutch function? MC fluid temp?

It sounds like the clutch is working OK -the way I read it, he's depressing the clutch pedal to rev the engine up without a load on it, then engaging the clutch at a higher rpm where the overheating engine now has enough power to take the load without stalling.

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Ohiospider1975 Avatar
Ohiospider1975 Warren Brown
Findlay, OH, USA   USA
I am not a sadist and this is not a joke. I flew to Florida to take possession of this MGA. I had purchased it in December while it was still in a British Car Garage there. I had the wiring harness replaced and any problem other issues resolved by the same British Car Garage near Sarasota airport.

So, I wanted to drive the vehicle. My plan was to drive it, park it at my brother's condo, and then in March have someone trailor it back to Ohio. That still is my plan. But, immediately on Friday afternoon I started facing these unanticipated engine issues. I had just been told by the garage owner that the car checked out fine. I decided on Saturday I was going to drive from Sarasota over to Long Boat Key, back up along the islands to Bradenton Beach and then back down Tamiami Trail to Sarasota. Well, I konked out several places. Once in front of the Sarasota Exotic Car Show outdoor display. People thought my car was part of the display and they pushed me out of traffic to the curb. Another konk out at a two lane draw bridge that went up. I made lots of friends with the cars backed up behind me. Several waved their fingers in appreciation. Other times, I was able to swerve out of traffic to park it along the beachfront or golf course to rest and cool. I had to reposition the car for transit north next month and I was not leaving it in the garage where I was continually told everything is fine.

But, problems need to be solved. So, I asked for your input. Thanks again.

Ohiospider1975 Avatar
Ohiospider1975 Warren Brown
Findlay, OH, USA   USA
Yes, the Clutch is fine..just getting abused, that is all. As Henry understood, I was using the clutch to increase engine RPMs to get up to where I had some engine power (3500-4500 RPM). In addition, when I would restart, I noticed small gasoline drip along the front of the carberetters spindle throttle near the float chamber onto the heat shield below.

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Neil MG Avatar
Neil MG Neil McGurk
Cumbria, UK   GBR
1956 Morris Minor
1958 MG MGA
1960 MG MGA
1961 MG MGA    & more
It might not be the temperature causing the problem, although it is running too hot and that needs to be sorted out. It may be the condenser that is failing when hot, that could cause your symptoms.

Gary E Avatar
Gary E Silver Member Gary Edwards
Kernersville, ,N.C., USA   USA
A bad coil will also fail when heated. You need to get the correct radiator cap also. You need a 7 lb cap with a 1 1/8" reach. The MGA radiator is deep throat-ed and a short cap will not seal resulting in boil over at 212°.

You might try emailing Barry Alexander VP of the Suncoast British Car Club and ask for shop recommendations.


Edited 1 time(s). Last edit at 2012-02-20 02:40 PM by Gary E.

Taylor Blair Avatar
Austin, TX, USA   USA
Warren... Sorry I can't give you a good answer. I can on the other hand relate to a lot of what you are saying. I used to dread stop lights and the gauge I watched the most was the temp gauge.

I ended up doing several things, some if not most will tell you I wasted my time and money but I feel better with the car and it seems to behave.

1. I put a temp gauge up from the local auto parts place under the dash so I could tell what was really going on. A pegged stock gauge was really about 210.
2. I wrapped the exhaust manifold.
3. I had a machinist at work cut me two exhaust shields using the stock one as a template. I used the stock carb spacer in between the two aluminum shields. That helped the surging and lack of power.
4. I replaced the radiator. I guess I could have had my original one redone but I felt better with a new one, I got an aluminum one. People on here get into a pissin' contest about what will transfer heat better but I went with what I felt most comfortable with. Changing that really helped with the temps.

Now on a stadard day I run about 160... dead of Summer at 110 I might, might touch 190.

Hope you get it going and if you are ever out in Texas drive by and we'll wave at you with that one finger of appreciation.

Take care,

jackalley Avatar
jackalley Jeff Allen
Mass, USA   USA
Maybe a few issues non related...

I had overheating issues that needed to be sorted out (missing felt pad under the hood, missing air ducts, etc) Barny had a good list and with all those done my overheating issues went away.

I also had a lack of power once and it was due to a bad/leaking float in the front carb? Take off the top of the float chamber, shat the float, and see if the float had any gas in it...

barneymg Avatar
barneymg Barney Gaylord
(Somewhere in USA), Pick one (or more), USA   USA
1958 MG MGA "MGA With An Attitude"
A broken or loose water pump impeller will cause those symptoms, like this:

When water does not circulate it will overheat the cylinder head, and it may not even show on the temperature gauge. I once had a frozen generator the stopped rotation of the fan belt and water pump. At highway speed the temperature gauge read 190dF while the engine was losing power rather dramatically, and it was not from hot carburetors.

It turned out that a new generator pulley with integral fan the I had just installed was fouling on the belt tension bracket bolt head. After I clipped the corners off of all the fan fins to clear the bolt head, all was well again.

Barney Gaylord - 1958 MGA with an attitude - -

2mgs4doors Avatar
2mgs4doors Harry Rathvon
Lancaster, PA, USA   USA
I've had vapor lock problems( i'm blaming ethanol in the fuel) the past several years with my MGA coupe and 20 minutes was about the same time it took to cool down enough to get it restarted. Then again something else was festering that took some time to come to a head!....Last summer it started running bad and i was assuming vapor lock again......well i couldn't get it going and had to get it towed home.....problem....bad rotor...lots of talk in the past here about a bad batch of did last for about 5 or 6 years but i don't put many miles on it.....I also had the cracked float in the TR6 that filled with gas and sunk,had me baffled for quite some time..another thing to think about these days if old gas......i was told that gas loses about 1 point of octane a month....My MGTD suffered from this a couple years ago and just didn't run gas cured that !

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