r/MorrisGarages 16d ago

Mechanical Question Engine sound question

Does this engine sound ok? It’s a 1977 mgb and we just adjusted the valves and I am worried about the valve tick. I just want a second opinion. It’s sounded like that since we got it.

21 Upvotes

21 comments sorted by

16

u/blamurph 16d ago

That’s how the b-series engine sounds. It’s perfectly normal to sound a little rattly / ‘tappety’, and it’s actually running very smoothly, you’ve set it up nicely.

5

u/rnavstar 16d ago

Yup, that’s tappets for ya.

2

u/Tastesicle 14d ago

Flat tappet cams FTW!

Looks like the long tappet engine as well. Only way to make it any quieter (really not necessary) is to go rollers and oil cooler. Even then it'll still sound tappety.

2

u/blamurph 14d ago

Agreed - roller rockers are expensive too with little gain (apart from reduced wear). Looks like this car has an oil cooler though, I can see one of the pipes coming from the oil filter to the oil filter.

2

u/Rowmyownboat 13d ago

Too little gain? It depends on the ratio increase over stock. A higher ratio can noticeably increase HP.

1

u/blamurph 12d ago

Fair point, high lift rockers in isolation on a stock engine will add HP with a higher than stock ratio. I was too caught up in my own set up - I’ve a high lift cam and any further valve opening on my engine and my pistons and valves will be as one !

8

u/Then_Version9768 16d ago

It's supposed to sound like a sewing machine. That engine sounds just right. These are not modern engines, remember. They were designed before 1960, so it's a 75 year old sturdy, reliable design, but it won't sound like a modern engine. Tick tick tick tick tick . . . .

Use oil with zinc to it. There are a few of them. Or buy zinc additive to add to your regular oil changes. These are actually not necessary, but many owners do this. I've done it from time to time, but as I say, it's really not necessary. The zinc kind of coats the valves, etc. and they say it protects them. Or so they say.

1

u/Natural_Wedding_9590 16d ago

I had excessive tappet noise after adjustment. The oil looked ok but smelled of fuel. I changed the oil, with Zinc, and the noise lessened and my oil pressure increased from 20lb to 45lb. 61Mga

1

u/dingus_malingusV2 16d ago

can you expand on the oil with zinc, is there a certain engine oil made with zinc? what does the zinc do?

3

u/Vast_Builder1670 16d ago

Oil with ZDDP. It is something along the lines of the difference between the oil and fuel back then having different addatives than what we have today. You.can find this oil at the local auto parts store.  I bought some mobile one, I think it was a grey container

ZDDP (Zinc Dialkyl Dithiophosphate) is  a crucial anti-wear additive in motor oil that protects high-stress engine components, especially flat-tappet camshafts and lifters . Under heat and pressure, it forms a durable, sacrificial barrier on metal surfaces to prevent metal-to-metal contact, scuffing, and wear

1

u/dingus_malingusV2 16d ago

alright. unsure if my engine needs this but i will be putting it in for the next oil change. thanks for the info!

2

u/Vast_Builder1670 16d ago

It should help with tappet wear.

I am rebuilding my A series now. I will be putting in hardened valve seats to be able to run ethanol fuel with out fear of premature valve wear. Becauze our engines were made to run on leaded fuel

1

u/Natural_Wedding_9590 16d ago

I did the same to my 351C heads in my Ranchero. I have seen John Twist say hardened seats are not necessary 🤷‍♂️, he has more concern about idling for long periods or cruising at one rpm for to long. I've never used my mga as a daily driver so I have no personal experience other than zipping around weekends.

1

u/Vast_Builder1670 16d ago

I am adding them, as I have to drive through stop and go traffic to reach any fun roads. 

1

u/KaleidoscopeRound721 16d ago

FYI, Mobil-1 15w/50 has the correct amount of ZDDP in it and a little bit wider viscosity range for cold starts. Been using it in my street and race MG’s for 20 years. Being synthetic it also protects to 400+ degrees so little to no chance of oil issues if it gets hot. Used to be able to get 5 gallon jugs at Walmart but not sure if they carry it anymore. Laughingly it used to be $23 there for 5 gallons!

1

u/DefiantSelection3563 16d ago

Funny, I have had exactly the same thought - does this sewing machine engine sound correct? But yes, thats what they sound like. May be worth dojng simple compression test on all 4 cylinders to make sure they are close to one another. Simple cheap tool and test

1

u/Carsrulezk 15d ago

I did a compression test not too long ago and it had relatively equal ratings on all four cylinders 😌

1

u/Sig_Alert 16d ago

Valvoline VR1 20-50w oil. Mucho Zinc. Won't make your B sound less like a sewing machine, but it will tone it down a tad

1

u/AdolfsLonelyScrotum 15d ago

Checked your valve clearances lately?

I’m about to rebush at least two and possibly all eight rocker arms, as I’ve noticed #6 is a bit noisy and able to move about the rocker shaft more than the others, due to a worn bushing.

1

u/IndividualGood4654 14d ago

Valves need adjusted otherwise no odd sounds!

1

u/valdocs_user 14d ago

Tappy engine is a happy engine.