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3800 series 2 broken timing chain advice


jamin022
01-24-2010, 02:10 PM
hi. i have a 2000 park ave. it decided not to start one day.this is where the nightmare begins...after checking the usual suspects (fuel and spark) i was determined it was the crank sensor.so i towed it to a shop to have it scanned.and found out that the sensor was good and it was the timing chain that was broke.the mechanic said the damage was caused from driving it with a leaking intake gasket. so anyhow he says that the engine is not worth fixing and i should install a new engine.this engine cranks fine and the oil is showing very little signs of coolant. it has 103.xxx mile on it. im thinking of installing a new chain set and intake gaskets and flushing the oil out. but i am worried that down the road it will spin a bearing or something.so now i am not sure if i should fix this engine or just drop a used junkyard engine.i am not real familiar with this 3800 series 2 so any advice would be much appreciated. thanks.:runaround:

MagicRat
01-24-2010, 02:45 PM
Coolant in the oil will not cause a timing chain to break. They are, imo, 2 completely different issues.

Usually, coolant in the oil is obvious, the oil looks like a green-brown milkshake. If the oil looks normal, you may not have a leak at all. Imo have the existing engine oil analyzed by a lab if it looks normal to verify the condition.

As for the timing chain..... usually these do not actually break, the timing chain simply gets very loose and eventually skips one tooth, causing the valve timing to go out of synch. In this case, a new chain and sprockets will put everything right.

If the chain really and truly has broken, then its likely one or more valves are bent, since they will probably have hit a piston. If this is the case, the cylinder heads must be removed and repaired.

jamin022
01-24-2010, 03:13 PM
ok.thanks for the input.looks like i got my work cut out for me.i don't think the chain is actually broke. the engine cranks fine but you can tell it's out of time.you can hear the backfire from the air intake.i would think that if it had a bent valve it would be making noise or turning over hard .i have to get out there and start tearing this thing down.i may have to wait till spring.my garage is full and it's cold out there. thanks again.

Jrs3800
01-24-2010, 05:46 PM
Pop the oil cap off, look at the rockers when someone turns the motor over... Do the rockers move? Does the motor turn over like it has compression?

And did they replace the crank sensor?

It is extremely rare for a timing chain to break or jump time on these motors, the Tensioner for the chain is pretty good and I have pretty much never seen a series II jump time..

jamin022
01-24-2010, 06:32 PM
they did not replace the sensor.i was the one cranking while the mechanic was checking the rockers.he looked up at me and said it's your timing chain gear.i did see the scanner readings and it said that the sensor was reading.this is all i got for my 50 bucks diagnosis fee.then he said that i should replace the engine.i .he also pulled the dipstick and said it looked milky but it did not look that bad to me.(maybe a little milky).but i know that the intake gasket has been leaking for a while and i have been putting that repair off.i think my laziness caught up with me.i towed the car back home after he quoted me 1200 bucks for a 63.000 mile engine. but i called the junk yard and that exact engine is only 550 bucks.so i figured i would install myself if thats the case.i guess the question is how strong is this engine and is it salvageable once it gets dexcool in the oil.and if the nylon gear is broke whats the odds of having to remove the heads. thanks for the info.

Jrs3800
01-24-2010, 06:55 PM
I am hopeful that you have an LKQ or a good local yard near you..

If the motor is as bad as you think it is, Look for a 3800 Series III L26, this is not a sought after motor...

Its the same block as what you have, with better rods and pistons and better flowing heads... The largest difference is that its Drive By Wire... all you would have to do is park you upper intake and parts on it and possible swap a couple of sensors..

I do not use Series II 3800's in replacements, I always try to find a series III... Here where I am I can easily get a very low mileage series III 3800 for $250...

I always look up the motor for an 06-07 Pontiac Grand Prix Vin 2


also is your Park Ave Naturally Aspirated or Supercharged?

danielsatur
01-24-2010, 06:59 PM
I would do my own compression check on all cylinders, befor getting to excited.
What's imo?
If the timing chain broke, it wouldn't run with 1/2 the engine gone!

jamin022
01-24-2010, 07:14 PM
that's great advice.the yards here are a little pricey.i will check on a series 3 tomorrow for sure. my 2000 pa has a normal engine (not supercharged) its a vin code# k.i cant wait for the weather to break so i can look in to this engine.and see if this mechanic is trustworthy.im hoping to salvage the original 3800.i guess i will know once i get the top torn down. thanks for your advice.

jamin022
01-24-2010, 07:18 PM
yes i will have to do a complete compression check. thats one tool i do not own i guess i will have to invest in a new gauge. thanks

tempfixit
01-24-2010, 08:04 PM
Would this 3800 Series III engine work in 96 Buick Lasabre??

thanks

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