Engine, smooth with no load, lawn mower under load

[Dj7291993]

Ok, so I just got my car driving again (so glad to be done with that transmission), time to look at the engine. When the car is under no load (decelerating, even throttle to just below what it takes to accelerate), the engine sounds smooth... loud (holes in exhaust), but smooth. But try to accelerate, and it sounds like a lawn mower. Why?

 

Plug wires, plugs, air filter, oil filter, and oil are all new. Planning on doing the seafoam next week (want to figure out my new mpg first).

 

Info:

'87 GL coupe, 1.8L EA82 Carb. Originally an auto, now a 5-speed d/r. 118k miles.

[Dj7291993]

Also, I think my is not choke shutting off, as my idle stays at 1750-2000rpm, but it isn't always there. And, when I tap the gas, it doesn't change it.

Edited March 15, 2011 by Dj7291993
poor grammar

[Twitch de la Brat]

It could very well just be the holes in the exhaust.

My EA82 would sound like a lawn mower most of the time with it's exhaust

leaks, but it was pretty quiet, just as you described, while idling.

 

Twitch

 

EDIT: The choke not closing could be part of it, as it can often cause it to run

rich and allow for unburnt fuel to get to the exhaust leaks and self ignite.

But that would be backfiring as well, not just loud exhaust.

Edited March 15, 2011 by Twitch de la Brat
Poster added more details

[987687]

Don't ea82s always run like lawn mowers....?

 

If your timing is off it won't run right, I've been through that.

[Deener]

Speaking of lawnmowers, how handy would it be to have a 'pull start' option?

 

Lawnmower sound...check your exhaust gaskets/studs (right where they meet at the heads). If the gaskets are toast or you have a loose or missing bolt, the sound will be similar to a lawnmower. The nuts should be a 14mm deep socket if they are the originals. Holes...yes they will do that too but you might be able to quieten it down a bit by securing the studs/nuts to the heads. Proceed with caution though...you don't want to strip the studs or the nuts.

[Dj7291993]

just checked the gaskets. It does back fire when the engine speed drops rapidly (like when shifting). And I've heard some that sound quieter in that regard, but they tend to tick (which, thank God, mine doesn't). If it's just the exhaust, then I'm gonna leave it alone. About $200 to fix that.

[Twitch de la Brat]

just checked the gaskets. It does back fire when the engine speed drops rapidly (like when shifting). And I've heard some that sound quieter in that regard, but they tend to tick (which, thank God, mine doesn't). If it's just the exhaust, then I'm gonna leave it alone. About $200 to fix that.

 

Actually, if you're willing to do the work, it's not that hard.

You just need to see which exhaust studs are loose and helicoil them, or tap them out to a larger size and make studs to fit.

 

Also, new gaskets are always a good idea if yours are old or burnt.

 

Twitch

[Dj7291993]

I just changed the gaskets with new dealer ones when I changed my transmission, and all of the studs were tight, and all stayed in. Sorry, tried to say that in the last post, but guess I didn't communicate that very well (really should try that "sleep" thing).