Chasing Engine Noises In Your Classic Car - Part 1

[@johnsharonwhitaker9242]

Hi GT guy, Rod knock vote here also. My first car was a '53 Austin bought in 1960. Went onto 3 cylinders. My pal's dad was an army mechanic and he took us through fixing it and started a lifetime hobby in me. broken ring had worn a groove in a cylinder. sleeved it, ground the crank, did the head. 100 miles later threw a rod. Disassembly and metallized the journal and all back together. 800 miles later did it again. took it to a guy with a one armed bandit which would grind a rod journal with engine in the car. but too badly worn. Finally learned you can't drive those old Brits at 60 mph. John in Manitoba.

[@MGB-learning]

Always an Outstanding video and presentation.

[@mgbgtguy]

I appreciate it, glad you enjoyed it!

[@fredknoch]

Thanks for the video! I have a concerning sound on my mg midget 1275 a series engine that I’ve been reluctant to diagnose (fear of the potential $$$). This video is just what I needed to start the process.

[@mundanestuff]

Good info, had a buddy ignore the noise on the bottom end, wound up losing his crank shaft, and as you know, a crank shaft for an XPAG is not easy or cheap to find.

[@michaelstoliker971]

We had a "Fully Restored" MG-TC brought to our shop. I was driving the car around the block to evaluate it when it suddenly started knocking. I checked everything out and dropped the pan. When I went to look under the car I bumped the flywheel and it moved. The bolts had backed out of the crankshaft and had gotten beat up. The threads were ruined...maybe they were already ruined and that's why they backed out. We had to order new bolts from England because they are very unique French Metric bolts. We put them on with loctite and they stayed put. I had other problems with that car including being stranded on the side of the road because there was no gas in it and the indicator wasn't working! I'd never own a T-series MG, too crude.

[@mgbgtguy]

The flywheel is on the list to check once the pan is off. What makes those bolts unique is they are metric, but with Witworth heads. Lord Nuffield bought a nut and bolt factory in France and wanted to utilize it. When the XPAG engine was tooled up they used all metric hardware, but made it with the Witworth stock so the dealer mechanics could still used the tools they already had. It’s often referred to as “the mad Nuffield design”. All hardware can be substituted with equivalent metric hardware that is much easier and cheaper to get. Of course then you need both metric and Witworth tools to work on them in that case. There’s lots of cars running around with a mix of both

[@stephenhenion8304]

You mean to tell me, after all these years that MG'S are all running around with mixed up nuts and bolts!! I never....

[@michaelstoliker971]

@@stephenhenion8304 And not just the ones behind the wheels.

[@ianrenshaw6653]

You mentioned that he put on a new muffler system. Perhaps some part of the exhaust system is vibrating and hitting something resulting in the knock? Cheers Ian

[@americanpatriot2422]

Great video

[@mgbgtguy]

Thanks!

[@laurierasmussen2244]

Try the harmonic balancer.

[@bshnabel]

Nice car, thanks

[@stephenhenion8304]

Someone should tell the owner, Okay, I'll tell the owner... Take back roads, stay OFF the highway. Drive your car within its designated operating parameters. Enjoy the ride.... spend less time at the show, and more time cruising... had my Sprite for 11 years.. i loved it!!!

[@mgbgtguy]

I already warned him that these things don’t like cruising about 4000 RPMs, he should’ve been taking the back roads, and that he might’ve knocked the bearings out of it.

[@MrAvant123]

Big end bearing for sure wouldnt describe this as a 'grumble' .

[@mgbgtguy]

In person, it does sound more like a grumble, and less like a knock than the mic is picking up, I was actually surprised at how different it sounded when I went to edit the video than it did in person.

[@michaelstoliker971]

Check the flywheel.

[@huntdowse9727]

Would he be able to add an overdrive to the transmission?

[@mgbgtguy]

There is no overdrive that I know of for these, but there are five speed transmission conversions available (but they are expensive). You can also some modifications swap out the original 4:88-1 gear set for the MGA 4:30-1. That really helps lower the RPMs, while cruising, but at the sacrifice of a bit less low end grunt around town.

[@herschelmayo2727]

Impossible to find competent machine work for an antique four cylinder. They all want to work on monster V8s and give the job to the latest hire, who resents doing it and turns out a bad job. My job? Two rods with the crank bearing bored cockeyed, crank journals ground tapered, one cylinder bored curved. Don't ask me how, I have no idea. Finally took it to a world-class machine shop with laser equipment that told the tale.

[@mgbgtguy]

I have a pretty good machinist that I use, unfortunately though, he’s always backed up and can sometimes be pretty slow 😁

[@andrewwmacfadyen6958]

Any mechanic can identify that knock in 5 seconds from 30 yards away.

[@mgbgtguy]

Well, the point of the video is for those who aren’t seasoned mechanics to be able to try to identify different noises, not to just say hey look this things got a rod knock in it.

[@toddmackey4374]

rod knock

[@ThomasPrior-wv6zn]

any up date on the riley rme